GENTAMICIN SULFATE

General Administration Information
For storage information, see the specific product information within the How Supplied section.

Route-Specific Administration

Injectable Administration
-Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.
Intravenous Administration
Intermittent IV Infusion
Dilution/Preparation
Vials for Injection
-Concentrated solutions (10 mg/mL and 40 mg/mL) may be diluted in 0.9% Sodium Chloride Injection or 5% Dextrose Injection prior to IV infusion.
-Dilute to a convenient volume (usually 1 mg/mL or less).

Premixed IV Solution
-Administer as a secondary medication unit.
-Check for leaks by squeezing bag firmly. Do not add supplementary medication.
-Adjustments may be made to premixed containers to either add or remove contents to provide an appropriate dose.
-Attach to administration set. Do not introduce additives to the solution
-Do not use plastic containers in series connections as this could result in an embolism due to residual air being drawn from the primary container before administration of the fluid from the secondary container is complete.

Intermittent IV Infusion Administration

-Infuse IV over 30 minutes to 2 hours; usual infusion time is 30 to 60 minutes.
-Do not physically premix with other drugs.


Intermittent IV Push*
NOTE: Gentamicin is not approved by the FDA for IV push administration. IV push administration is generally not recommended in pediatric patients.
Dilution
-Variable preparations have been reported in the literature for adult patients. Dilutions include doses less than 800 mg diluted with 0.9% Sodium Chloride Injection to a total volume of 20 mL, 120 mg doses diluted with 50 mL of 5% Dextrose Injection or 0.9% Sodium Chloride Injection, 80 mg diluted in 2 mL of 0.9% Sodium Chloride Injection (40 mg/mL), and doses diluted with 0.9% Sodium Chloride Injection to a total volume of 20 mL.
-Storage:
--In one study, gentamicin (40 mg/mL) stored propylene glycol syringes retained potency for 30 days when stored at 4 degrees C and 25 degrees C.
-Another study showed gentamicin (40 mg/mL) stored in plastic syringes had an average potency loss of 16% at 30 days at both 4 degrees C and 25 degrees C. Gentamicin (40 mg/mL) stored in glass syringes had an average potency loss of 7% at 30 days at both 4 degrees C and 25 degrees C. In both instances, a brown precipitate formed.


Intermittent IV Push Administration

-An IV push rate of 3 to 5 minutes has been reported in pediatric patients.

Intramuscular Administration
-Do not use solutions prepared from commercially available premixed solutions for IM administration.
-Withdraw appropriate dose directly from the vial of solution for injection. No dilution necessary. Inject deeply into a large muscle mass.



Topical Administration
Cream/Ointment/Lotion Formulations
Topical Cream or Ointment
-Rub cream or ointment gently into cleansed affected area. Care should be taken to avoid further contamination of the infected skin.
-Treated areas may be covered with sterile gauze if desired.
-Crusts from impetigo should be removed before application to permit maximum contact between the antibiotic and the infection.
-Use of topical gentamicin under gelatin packing may be used for infected stasis ulcers.



Inhalation Administration
NOTE: Gentamicin is not FDA-approved for inhalation administration.

Reconstitution
-0.9% Sodium Chloride Injection has been used as a diluent.
-80 mg of gentamicin diluted to achieve a total volume of 4 mL has been described.

Nebulization*
-Consider pretreating with a bronchodilator.
-Various nebulizers have been used.
-The dose should be nebulized and inhaled over 10 minutes.


Ophthalmic Administration
Ophthalmic Solution or Ointment
-Apply ophthalmic solution or ointment topically to the eye.
-Instruct patient on appropriate installation technique.
-Do not touch the tip of the dropper or tube to the eye, fingertips, or other surfaces.
-To prevent contamination, each dropper is for one individual, do not share among patients.

Nephrotoxicity (azotemia) is a well-known adverse reaction to gentamicin and other aminoglycoside antibiotics. Additional reported adverse renal effects include pyuria (increased WBCs), proteinuria, cylindruria (cells or casts in the urine), increased BUN, NPN, or serum creatinine, and oliguria. Aminoglycoside antibiotics are taken up by lysosomes in cells lining the proximal tubule, which, in turn, leads to necrosis and/or fibrosis. With continued exposure, interstitial fibrosis, renal tubular necrosis, and renal tubular acidosis (RTA) occur. If aminoglycoside therapy is discontinued prior to this, renal dysfunction can be reversible. Various studies have identified risk factors for developing nephrotoxicity from aminoglycosides: excessive trough serum concentrations, use of other nephrotoxic agents, total dose or treatment duration, and preexisting renal disease. Monitor laboratory markers of renal function and urine output carefully.

Ototoxicity can occur during gentamicin therapy due to eighth cranial nerve toxicity. This can be manifested as high-frequency hearing loss, tinnitus, vertigo, or dizziness, since either auditory or vestibular toxicity is possible. These manifestations may be permanent. Hearing loss is usually manifested by diminishing high-tone acuity. Factors that increase risk of ototoxicity include excessive dosage, dehydration, and previous exposure to other ototoxic drugs. Audiograms should be performed in patients who receive repeated or prolonged courses of therapy with gentamicin.

Neurotoxicity has been reported with gentamicin therapy. Peripheral neuropathy or encephalopathy, paresthesias including numbness or skin tingling, muscle twitching, tetany (in neonates), convulsions, and a myasthenia gravis-like syndrome with muscle weakness, have been reported.

In general, administration of parenteral gentamicin is well tolerated; however, injection site reaction can occur with intramuscular or intravenous administration. Venous thrombosis, phlebitis, extravasation, and hypervolemia at the site of injection have been reported but may be related to administration technique. Occasional reports of pain at the injection site as well as rare subcutaneous atrophy or fat necrosis, suggesting local irritation, have been noted.

Systemic gentamicin has been possibly associated with pseudotumor cerebri, causing benign increased intracranial pressure. The exact incidence of this adverse effect is unknown. Additionally, lethargy, confusion, depression, headache, and acute organic brain syndrome have been reported. Hallucinations have rarely been reported with the use of the ophthalmic preparations of gentamicin.

Rash (unspecified), itching, urticaria, purpura, alopecia, and generalized burning have been reported during trials with systemic gentamicin. Thrombocytopenic purpura has also been reported with the ophthalmic preparations of gentamicin. In patients treated with topical gentamicin, local skin irritation (erythema and pruritus) occurred, but did not usually require discontinuance of therapy. Possible photosensitivity has also been reported with the topical products; however, this response could not be duplicated with reapplication of gentamicin and exposure to ultraviolet radiation.

Gastrointestinal adverse reactions that have been reported to be possibly associated with systemic gentamicin include decreased appetite, weight loss, nausea, vomiting, increased salivation (hypersalivation), and stomatitis.

Respiratory depression and pulmonary fibrosis have potentially been associated with systemic gentamicin therapy. Neuromuscular blockade may be one mechanism by which respiratory depression may occur. Aggravating factors for neuromuscular blockade include the concurrent use of neuromuscular blocking agents or other drugs known to have neuromuscular effects. If neuromuscular blockade occurs, calcium salts may reverse it.

Elevated hepatic enzymes (SGOT, SGPT), increased LDH, and hyperbilirubinemia have been noted with systemic gentamicin. While clinical laboratory test abnormalities may be isolated findings, they may also be associated with clinically related signs and symptoms. For example, transient splenomegaly and hepatomegaly have possibly been associated with gentamicin therapy.

Fever and joint pain (arthralgia) have been rarely associated with gentamicin therapy. Fever may indicate untreated/resistant infection or the presence of a new infection, but the drug may also be associated with drug-induced fever.

Laryngeal edema and anaphylactoid reactions have been associated with gentamicin therapy. Allergic reactions have also occurred with the ophthalmic preparation of gentamicin.

Hypotension and hypertension have been rarely reported as possibly associated with systemic gentamicin therapy.

Hypocalcemia, hypomagnesemia, hyponatremia, and hypokalemia have been possibly associated with gentamicin therapy. These laboratory abnormalities may be isolated findings or may be associated with clinical symptoms such as muscle weakness. Electrolyte imbalances may also be associated with renal adverse effects of gentamicin. Correct electrolyte abnormalities, as they may increase the risk for neuromuscular weakness.

Anemia, leukopenia, granulocytopenia, transient agranulocytosis, eosinophilia, increased or decreased reticulocyte counts, and thrombocytopenia have all been potentially associated with gentamicin therapy. While clinical laboratory test abnormalities may be isolated findings, they may also be associated with clinically related signs and symptoms.

The most frequently reported adverse events associated with ophthalmic administration of gentamicin include ocular irritation and burning, conjunctivitis, conjunctival epithelial defect, and conjunctival hyperemia. Ocular administration of gentamicin has also resulted in the formation of bacterial and fungal corneal ulcers, and use of the ophthalmic ointment may result in impaired wound healing of a corneal lesion or abrasion. Visual disturbances have been noted with systemic gentamicin therapy.

Microbial overgrowth and superinfection can occur with antibiotic use. C. difficile-associated diarrhea (CDAD) or pseudomembranous colitis has been reported with gentamicin. If pseudomembranous colitis is suspected or confirmed, ongoing antibacterial therapy not directed against C. difficile may need to be discontinued. Institute appropriate fluid and electrolyte management, protein supplementation, C. difficile-directed antibacterial therapy, and surgical evaluation as clinically appropriate.

Patients receiving systemic aminoglycosides, such as gentamicin, should be closely monitored for nephrotoxicity. Aminoglycosides are associated with major toxic effects on the renal tubules. In patients with pre-existing renal impairment or renal failure or in those with normal renal function who receive high doses or prolonged therapy, the risks of severe nephrotoxic adverse reactions are sharply increased. Nephrotoxicity can manifest as decreased creatinine clearance, the presence of cells or casts, oliguria, proteinuria, decreased urine specific gravity, or evidence of increasing nitrogen retention (increasing BUN, NPN, or serum creatinine). When monitoring gentamicin serum concentrations, the FDA-approved product labeling states that prolonged peak concentrations above 12 mcg/mL and trough concentrations above 2 mcg/mL should be avoided. Single-daily dosing regimens that produce higher peak serum concentrations have been used without additional toxicity noted; however, it is important to allow the trough concentration to decrease appropriately before redosing. Evidence of nephrotoxicity requires dosage adjustment or discontinuance of therapy. Hemodialysis may aid in gentamicin removal in the event of overdose or toxic reactions, especially if renal function is or becomes impaired. In rare cases, nephrotoxicity may not be evident until soon after completion of therapy. Aminoglycoside-induced nephrotoxicity usually is reversible. Avoid concurrent and/or sequential coadministration of aminoglycosides with other drugs that are potentially nephrotoxic and/or neurotoxic because toxicity may be additive. Use caution and monitor urine output and laboratory values carefully in neonates being treated for patent ductus arteriosus with an NSAID. Patients with dehydration are at increased risk of developing toxicity. In the event of toxicity in newborns, exchange transfusions may be considered. Intravenous diuretics may also alter aminoglycoside concentrations in serum and tissue and thereby enhance aminoglycoside toxicity.

Systemic aminoglycosides, such as gentamicin, are associated with neuromuscular blockade and may cause severe neuromuscular weakness lasting hours to days. Respiratory paralysis, respiratory insufficiency, or respiratory depression may occur when aminoglycosides are instilled after local irrigation and after topical application during surgical procedures. Neuromuscular blockade has also been reported with both oral and parenteral use of aminoglycosides. Clinicians should be aware of the possibility of neuromuscular blockade and respiratory paralysis if aminoglycosides are administered by any route with systemic absorption, especially in patients receiving anesthetics, neuromuscular-blocking agents (e.g., tubocurarine, succinylcholine, decamethonium), or in patients receiving massive transfusions of citrate-anticoagulated blood. Corrective therapy is required for any electrolyte imbalance, which may aggravate risk for neuromuscular/neurological symptoms. During or after aminoglycoside therapy, paresthesias, tetany, positive Chvostek and Trousseau signs, and mental confusion have been described in patients with hypomagnesemia, hypocalcemia, and hypokalemia. In infants, tetany and muscle weakness have been described. Aminoglycosides may aggravate muscle weakness in patients with neuromuscular disease such as myasthenia gravis, infant botulism, or parkinsonism.

Gentamicin is contraindicated in patients with aminoglycoside hypersensitivity. Allergic reactions to aminoglycosides are generally uncommon, but hypersensitivity with one agent may demonstrate cross sensitivity with another aminoglycoside. Some formulations of intravenous gentamicin contain sodium metabisulfite; therefore, patients with sulfite hypersensitivity should use parenteral gentamicin with caution. Sulfite sensitivity is seen more frequently in patients with asthma than non-asthmatic patients.

Consider pseudomembranous colitis in patients presenting with diarrhea after antibacterial use. Careful medical history is necessary as pseudomembranous colitis has been reported to occur over 2 months after the administration of antibacterial agents. Almost all antibacterial agents, such as gentamicin, have been associated with pseudomembranous colitis or C. difficile-associated diarrhea (CDAD) which may range in severity from mild to life-threatening. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.

Treatment with gentamicin may result in overgrowth of nonsusceptible organisms, including fungal infection or viral infection. If this occurs, appropriate therapy is indicated.

Monitor patients receiving systemic and inhaled aminoglycosides, such as gentamicin, for neurotoxicity, including ototoxicity and hearing impairment. Use aminoglycosides with caution in patients with preexisting hearing impairment, especially eighth-cranial-nerve impairment. Consider serial audiograms for high-risk patients. The risk of hearing loss increases with the degree of exposure (high or prolonged therapy), pre-existing renal impairment, concomitant or sequential nephrotoxic or ototoxic agents, dehydration, and advanced age. Patients with certain variants in the mitochondrially encoded 12S rRNA gene (MT-RNR1), particularly the m.1555A>G variant, may develop ototoxicity even when aminoglycoside serum concentrations are within the recommended range. These variants are present in less than 1% of the general US population, and the proportion of the variant carriers who may develop ototoxicity, including severe cases, is unknown. If there is a known maternal history of ototoxicity due to aminoglycosides or a known mitochondrial DNA variant, consider alternative treatments unless the severity of the infection and lack of alternatives outweighs the risk of permanent hearing loss. Discontinue therapy if there is evidence of auditory or vestibular toxicity. In the event of toxicity in newborns, exchange transfusions may be considered. When monitoring gentamicin serum concentrations during use of conventional dose regimens, avoid prolonged gentamicin peak concentrations above 12 mcg/mL and trough concentrations above 2 mcg/mL. However, single-daily dosing schemes that produce higher peak serum concentrations have been used without additional toxicity noted. Aminoglycosides are associated with major toxic effects on the auditory and vestibular branches of the eighth nerve. Auditory changes are irreversible, usually bilateral, and may be partial or total. Symptoms of ototoxicity can include dizziness, vertigo, tinnitus, roaring in the ears, and hearing loss and may manifest during therapy or after discontinuation. High-frequency hearing loss usually occurs before there is noticeable clinical hearing loss; clinical symptoms may not be present to warn of developing cochlear damage. Other manifestations of neurotoxicity may include numbness, skin tingling, muscle twitching, and convulsions.

Use of ophthalmic ointments, such as gentamicin ophthalmic ointment, may delay healing of corneal abrasion or lesions.

Neonates with hypoxemic ischemic encephalopathy (HIE) receiving hypothermia have significantly decreased clearance (25-50% lower) of gentamicin compared with nonasphyxiated, normothermic infants. A prolonged dosing interval is recommended in these infants to avoid supratherapeutic trough concentrations.

Description: Gentamicin is an aminoglycoside antibiotic that is active against aerobic gram-negative rods. It is also used in combination with other antibiotics to treat Staphylococcus aureus and certain species of Streptococcus. Gentamicin is active against certain Mycobacterium species but is not active against any anaerobic bacteria. Gentamicin is often used in combination with ampicillin as empiric therapy for neonatal infections. It is also used in combination with a penicillin for the treatment of endocarditis and with vancomycin for surgical prophylaxis (cardiothoracic and vascular procedures). Gentamicin is considered to be a narrow therapeutic index drug, and therefore, serum concentration monitoring is recommended for most regimens. The major toxicities of gentamicin include nephrotoxicity, ototoxicity, and neurotoxicity. Parenteral gentamicin is FDA-approved for use in pediatric patients as young as neonates. Other formulations of gentamicin (ophthalmic, topical) are FDA-approved for use in pediatric patients of varying ages depending on preparation.

Per the manufacturer, this drug has been shown to be active against most strains of the following microorganisms either in vitro and/or in clinical infections: Citrobacter sp., Enterobacter sp., Enterococcus sp., Escherichia coli, Haemophilus influenzae (beta-lactamase negative), Haemophilus influenzae (beta-lactamase positive), Klebsiella aerogenes, Klebsiella pneumoniae, Klebsiella sp., Neisseria gonorrhoeae, Proteus sp., Proteus vulgaris, Pseudomonas aeruginosa, Salmonella sp., Serratia marcescens, Serratia sp., Shigella sp., Staphylococcus aureus (MSSA), Staphylococcus epidermidis, Staphylococcus sp., Streptococcus pneumoniae, Streptococcus pyogenes (group A beta-hemolytic streptococci)
NOTE: The safety and effectiveness in treating clinical infections due to organisms with in vitro data only have not been established in adequate and well-controlled clinical trials.

This drug may also have activity against the following microorganisms: Acinetobacter sp., Aeromonas sp., Bacillus anthracis, Bartonella quintana, Brucella sp., Francisella tularensis, Morganella sp., Providencia sp., Yersinia pestis
NOTE: Some organisms may not have been adequately studied during clinical trials; therefore, exclusion from this list does not necessarily negate the drug's activity against the organism.

For the treatment of pulmonary exacerbations in patients with cystic fibrosis (CF)*:
Intravenous dosage:
Infants, Children, and Adolescents: 10 mg/kg/dose IV every 24 hours (Max: 660 mg/dose) initially, and then adjust dosage based on serum concentrations. Aminoglycosides have traditionally been administered as a three-times daily regimen such as 3.3 mg/kg/dose IV every 8 hours; however, high dose once-daily aminoglycoside regimens are now preferred. Of note, tobramycin is usually the preferred aminoglycoside for CF exacerbations because of its increased activity against Pseudomonas aeruginosa. Additionally, gentamicin has been associated with an increased risk of precipitating acute renal failure in CF patients compared with tobramycin.

For the treatment of infective endocarditis:
NOTE: Base aminoglycoside dosage on an estimate of lean body mass. Adjust dose based on serum gentamicin concentrations.
-for the treatment of native valve endocarditis due to viridans group streptococci* and nonenterococcal group D streptococci relatively resistant to penicillin:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 weeks. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of prosthetic valve endocarditis due to viridans group streptococci* and nonenterococcal group D streptococci relatively resistant to penicillin:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 6 weeks. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of endocarditis due to group B, C, F, and G streptococci*:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 2 weeks plus penicillin G, ampicillin, or ceftriaxone for 4 to 6 weeks.
-for the treatment of native valve endocarditis due to Staphylococcus sp.:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 3 to 5 days plus nafcillin/oxacillin or vancomycin for 4 to 6 weeks. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of prosthetic valve endocarditis due to Staphylococcus sp.:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus oxacillin/nafcillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus oxacillin/nafcillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 2 weeks plus nafcillin/oxacillin, vancomycin, or daptomycin plus rifampin for at least 6 weeks. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of native or prosthetic valve endocarditis due to penicillin-susceptible Enterococcus sp.:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 to 6 weeks plus penicillin G or ampicillin.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 4 to 6 weeks plus penicillin G or ampicillin.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 4 to 6 weeks plus penicillin G or ampicillin.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 4 to 6 weeks plus penicillin G or ampicillin. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of native valve endocarditis due to penicillin-resistant Enterococcus sp.* or in patients unable to tolerate beta-lactams:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 6 weeks plus vancomycin.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 6 weeks plus vancomycin.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 6 weeks plus vancomycin.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 6 weeks plus vancomycin.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 6 weeks plus vancomycin.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 6 weeks plus vancomycin.
-for the treatment of prosthetic valve endocarditis due to penicillin-resistant Enterococcus sp.* or in patients unable to tolerate beta-lactams:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 6 weeks plus vancomycin.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 6 weeks plus vancomycin.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 6 weeks plus vancomycin.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for at least 6 weeks plus vancomycin.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 6 weeks plus vancomycin.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for at least 6 weeks plus vancomycin.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for at least 6 weeks plus vancomycin.
-for the treatment of native or prosthetic valve endocarditis due to HACEK microorganisms*:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 weeks plus ampicillin.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 weeks plus ampicillin.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 weeks plus ampicillin.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 weeks plus ampicillin.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 weeks plus ampicillin.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 4 weeks plus ampicillin.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 weeks plus ampicillin.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 4 weeks plus ampicillin.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 4 weeks plus ampicillin.
-for the treatment of native or prosthetic valve endocarditis due to enteric gram-negative microorganisms:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 6 weeks plus a beta-lactam.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for at least 6 weeks plus a beta-lactam.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for at least 6 weeks plus a beta-lactam.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for at least 6 weeks plus a beta-lactam. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of native valve culture-negative endocarditis:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 to 6 weeks plus ampicillin; sulbactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 to 6 weeks plus ampicillin; sulbactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 to 6 weeks plus ampicillin; sulbactam.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 4 to 6 weeks plus ampicillin; sulbactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 4 to 6 weeks plus ampicillin; sulbactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 4 to 6 weeks plus ampicillin; sulbactam.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 4 to 6 weeks plus ampicillin; sulbactam. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 4 to 6 weeks plus ampicillin; sulbactam.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 4 to 6 weeks plus ampicillin; sulbactam or vancomycin with ciprofloxacin. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of early (1 year or less after surgery) culture-negative prosthetic valve endocarditis:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks.
Children and Adolescents: 1 to 2 mg/kg/dose IV every 8 hours for 2 weeks plus vancomycin, cefepime, and rifampin for 6 weeks. The FDA-approved dosage is 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of suspected Bartonella endocarditis* (culture-negative):
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus ceftriaxone for 6 weeks.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus ceftriaxone for 6 weeks.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus ceftriaxone for 6 weeks.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks plus ceftriaxone for 6 weeks.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks plus ceftriaxone for 6 weeks.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus ceftriaxone for 6 weeks.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks plus ceftriaxone for 6 weeks.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks plus ceftriaxone for 6 weeks.
Children and Adolescents: 3 mg/kg/day IV or IM divided every 8 hours for 2 weeks plus ceftriaxone with or without doxycycline for 6 weeks.
-for the treatment of documented Bartonella endocarditis*:
Intravenous or Intramuscular dosage:
Children and Adolescents: 3 mg/kg/day IV or IM divided every 8 hours for 2 weeks plus doxycycline for at least 6 weeks.
-for the treatment of endocarditis due to S. moniliformis or S. minus (rat-bite or Haverhill fever)*:
Intravenous or Intramuscular dosage:
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for at least 3 to 4 weeks plus penicillin G.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours for at least 3 to 4 weeks plus penicillin G.

For the treatment of skin and skin structure infections, including burn wound infection and necrotizing infections as well as minor skin infections, including folliculitis, furunculosis, impetigo, eczema, pyoderma gangrenosum, sycosis barbae, infectious eczematoid dermatitis, pustular acne, pustular psoriasis, infected seborrheic dermatitis, infected contact dermatitis, and infected excoriations:
NOTE: Base aminoglycoside dosage on an estimate of lean body mass. Adjust dose based on serum gentamicin concentrations.
-for the treatment of unspecified skin and skin structure infections:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
-for the treatment of necrotizing infections of the skin, fascia, and muscle:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours until further debridement is not necessary, the patient has improved clinically, and fever has been absent for 48 to 72 hours plus clindamycin or metronidazole for mixed necrotizing infections.
-for the treatment of minor bacterial skin infection including, folliculitis, furunculosis, impetigo, eczema, pyoderma gangrenosum, sycosis barbae, infectious eczematoid dermatitis, pustular acne, pustular psoriasis, infected seborrheic dermatitis, infected contact dermatitis, and infected excoriations:
Topical dosage:
Children and Adolescents: Apply a thin layer topically to the affected area(s) 3 to 4 times daily.

For surgical infection prophylaxis*:
Intravenous dosage:
Infants, Children, and Adolescents: 2.5 mg/kg/dose IV as a single dose within 60 minutes prior to the surgical incision; no intraoperative redosing is necessary. Guidelines recommend gentamicin, in combination with another appropriate antimicrobial (i.e., vancomycin, clindamycin, or metronidazole depending on procedure), as an alternate therapy for patients with beta-lactam allergy undergoing gastrointestinal, biliary tract, uncomplicated appendectomy, colorectal, urologic, or transplant procedures.

For the treatment of blepharitis, blepharoconjunctivitis, bacterial conjunctivitis, corneal abrasion*, corneal ulcer, dacryocystitis, keratitis, keratoconjunctivitis, and acute meibomianitis:
-for the treatment of blepharitis, blepharoconjunctivitis, bacterial conjunctivitis, corneal ulcer, dacryocystitis, keratitis, keratoconjunctivitis, and acute meibomianitis:
Ophthalmic dosage (ophthalmic solution):
Infants, Children, and Adolescents: 1 to 2 drops in the affected eye(s) every 4 hours; up to 2 drops in the affected eye(s) every hour for severe infections.
Ophthalmic dosage (ophthalmic ointment):
Infants, Children, and Adolescents: 0.5 inch ribbon in the affected eye(s) 2 to 3 times daily.
-for the treatment of corneal abrasion*:
Ophthalmic dosage (ophthalmic solution):
Infants, Children, and Adolescents: 1 to 2 drops in the affected eye(s) 4 times daily for 3 to 5 days.
Ophthalmic dosage (ophthalmic ointment):
Infants, Children, and Adolescents: 0.5 inch ribbon in the affected eye(s) 2 to 3 times daily for 3 to 5 days.

For the treatment of pelvic inflammatory disease (PID)*, including tubo-ovarian abscess*:
Intravenous or Intramuscular dosage (extended-interval dosing):
Adolescents: 3 to 5 mg/kg/dose IV or IM every 24 hours in combination with clindamycin IV as an alternative. Parenteral therapy should be continued for at least 24 to 48 hours after clinical improvement, and then stepdown to oral clindamycin or doxycycline for total of 14 days of therapy. When tubo-ovarian abscess is present, oral clindamycin or metronidazole plus doxycycline should be used for a total of 14 days of therapy.
Intravenous or Intramuscular dosage (conventional dosing):
Adolescents: 2 mg/kg/dose IV or IM loading dose, then 1.5 mg/kg/dose IV or IM every 8 hours in combination with clindamycin IV as an alternative. Parenteral therapy should be continued for at least 24 to 48 hours after clinical improvement, and then stepdown to oral clindamycin or doxycycline for total of 14 days of therapy. When tubo-ovarian abscess is present, oral clindamycin or metronidazole plus doxycycline should be used for a total of 14 days of therapy.

For the treatment of plague* infection:
-for the treatment of bubonic or pharyngeal plague*:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.
Neonates 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.
Infants, Children, and Adolescents: 4.5 to 7.5 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.
-for the treatment of pneumonic or septicemic plague*:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.
Neonates 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.
Infants, Children, and Adolescents: 4.5 to 7.5 mg/kg/dose IV or IM every 24 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

For the treatment of tularemia* infection due to exposure to Francisella tularensis in an individual patient or in a contained casualty setting:
NOTE: Streptomycin is the drug of choice to treat tularemia in most patients; however, because gentamicin is more widely available, it is an acceptable alternative.
Intravenous or Intramuscular dosage:
Infants, Children, and Adolescents: 2.5 mg/kg/dose IV or IM every 8 hours for 10 days. IV doxycycline, chloramphenicol, or ciprofloxacin could be used as third-line alternatives.

For the empiric treatment of febrile neutropenia*:
Intravenous dosage (extended-interval dosing):
Infants, Children, and Adolescents: 7 to 8 mg/kg/dose IV every 24 hours. In a pharmacokinetic analysis of data from a retrospective study in pediatric patients with febrile neutropenia, age-specific initial doses of 10.5 mg/kg/dose IV (1 year to less than 6 years), 9.5 mg/kg/dose IV (girls 6 years and older), and 7.5 mg/kg/dose IV (boys 6 years and older) given every 24 hours were recommended to achieve target serum gentamicin peak concentrations. Gentamicin, in combination with an antipseudomonal penicillin or cephalosporin, has been successfully used for the empiric treatment of febrile neutropenia in children. Guidelines for the management of fever and neutropenia in cancer patients recommend monotherapy with an antipseudomonal beta-lactam or a carbapenem as empiric treatment in high-risk patients; addition of a second gram-negative antimicrobial agent (i.e., aminoglycoside, aztreonam) is recommended for patients who are clinically unstable, when a resistant infection is suspected, or for centers with high rates of resistant pathogens.
Intravenous dosage (conventional dosing):
Infants, Children, and Adolescents: 2 to 2.5 mg/kg/dose IV every 8 hours. Gentamicin, in combination with an antipseudomonal penicillin or cephalosporin, has been successfully used for the empiric treatment of febrile neutropenia in children. Guidelines for the management of fever and neutropenia in cancer patients recommend monotherapy with an antipseudomonal beta-lactam or a carbapenem as empiric treatment in high-risk patients; addition of a second gram-negative antimicrobial agent (i.e., aminoglycoside, aztreonam) is recommended for patients who are clinically unstable, when a resistant infection is suspected, or for centers with high rates of resistant pathogens.

For the treatment of uncomplicated gonorrhea*, including cervicitis*, urethritis*, and proctitis*:
Intramuscular dosage:
Children weighing more than 45 kg and Adolescents: 240 mg IM as a single dose plus azithromycin as an alternative in patients with a cephalosporin allergy or when ceftriaxone is not available.

For the treatment of bacteremia and sepsis:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours. In neonates with hypoxic ischemic encephalopathy (HIE) receiving hypothermia, a gentamicin dosing interval of 36 hours has been recommended due to a lower gentamicin clearance in these patients. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours. In neonates with hypoxic ischemic encephalopathy (HIE) receiving hypothermia, a gentamicin dosing interval of 36 hours has been recommended due to a lower gentamicin clearance in these patients. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 12 hours. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response. Neonates younger than 37 weeks gestational age were excluded from the scope of the Surviving Sepsis Campaign guidelines.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours. Start within 1 hour for septic shock or within 3 hours for sepsis-associated organ dysfunction without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for de-escalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response.

For the treatment of meningitis and ventriculitis*:
NOTE: Serum concentrations should be used to guide dosage adjustments. In most patients, dosage of aminoglycosides should be based on an estimate of lean body mass.
-for the treatment of enterococcal meningitis*:
Intravenous or Intramuscular dosage (extended-interval dosing):
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours for 14 to 21 days as adjunct therapy.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours for 14 to 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours for 14 to 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 14 to 21 days as adjunct therapy.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 14 to 21 days as adjunct therapy.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 14 to 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 14 to 21 days as adjunct therapy.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 14 to 21 days as adjunct therapy.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 14 to 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 14 to 21 days as adjunct therapy.
Infants, Children, and Adolescents: 2.5 mg/kg/dose IV or IM every 8 hours for 14 to 21 days as adjunct therapy.
-for the treatment of group B streptococcal meningitis*:
Intravenous or Intramuscular dosage (extended-interval dosing):
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours for 14 to 21 days as adjunct therapy.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours for 14 to 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours for 14 to 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for 14 to 21 days as adjunct therapy. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 14 to 21 days as adjunct therapy.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 14 to 21 days as adjunct therapy.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 14 to 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 14 to 21 days as adjunct therapy.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 14 to 21 days as adjunct therapy.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 14 to 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 14 to 21 days as adjunct therapy.
Infants, Children, and Adolescents: 2.5 mg/kg/dose IV or IM every 8 hours for 14 to 21 days as adjunct therapy.
-for the treatment of meningitis due to L. monocytogenes*:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours for at least 21 days as adjunct therapy.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours for at least 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours for at least 21 days as adjunct therapy.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours for at least 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for at least 21 days as adjunct therapy.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for at least 21 days as adjunct therapy.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for at least 21 days as adjunct therapy. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 21 days as adjunct therapy.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 21 days as adjunct therapy.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for at least 21 days as adjunct therapy.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for at least 21 days as adjunct therapy.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for at least 21 days as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for at least 21 days as adjunct therapy.
Infants, Children, and Adolescents: 2.5 mg/kg/dose IV or IM every 8 hours for at least 21 days as adjunct therapy.
-for the treatment of meningitis or ventriculitis* due to gram-negative organisms:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for 10 to 21 days as adjunct therapy. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours. This dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours. This dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours. This dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours. This dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours for 2 weeks beyond the first sterile CSF culture or at least 21 days, whichever is longer, as adjunct therapy. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours. This dosing does not account for gestational age or birthweight.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours for 10 to 21 days as adjunct therapy.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours for 10 to 21 days as adjunct therapy.
-for the intrathecal* treatment of meningitis or ventriculitis:
Intrathecal dosage (preservative-free solution):
Infants, Children, and Adolescents: 1 to 2 mg intrathecally once daily. Use in addition to systemic therapy. Adjust dose as necessary based on gentamicin CSF concentrations and MIC of the organism.
-for the intraventricular* treatment of meningitis or ventriculitis:
Intraventricular dosage (preservative-free solution):
Infants, Children, and Adolescents: 1 to 2 mg intraventricularly once daily. Use in addition to systemic therapy. Adjust dose as necessary based on gentamicin CSF concentrations and MIC of the organism.

For the treatment of lower respiratory tract infections (LRTIs), including community-acquired pneumonia (CAP):
NOTE: Use lean body mass to calculate the gentamicin dose. Adjust dose based on serum gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 12 hours. This dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours. This dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dose is 2.5 mg/kg/dose IV or IM every 8 hours. This dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours.
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 36 hours.
Neonates 30 to 34 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 24 hours.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
-for the treatment of community-acquired pneumonia (CAP):
Intravenous dosage (conventional dosing):
HIV-Infected Adolescents: 2 to 2.5 mg/kg/dose IV every 8 hours for 5 to 7 days as an alternative in combination therapy for hospitalized patients at risk for P. aeruginosa.
Intravenous dosage (extended-interval dosing)*:
HIV-Infected Adolescents: 5 to 7.5 mg/kg/dose IV every 24 hours for 5 to 7 days as an alternative in combination therapy for hospitalized patients at risk for P. aeruginosa. A single study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.

For the treatment of intraabdominal infections (i.e., appendicitis, peritonitis, necrotizing enterocolitis):
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. One study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations. Guidelines recommend gentamicin, in combination with other appropriate antimicrobial agents (typically ampicillin and clindamycin/metronidazole), for complicated, community-acquired intra-abdominal infections. Treat for 4 to 7 days.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption. Guidelines recommend gentamicin in combination with ampicillin and metronidazole for necrotizing enterocolitis in neonates.
Infants: 2.5 mg/kg/dose IV or IM every 8 hours. Guidelines recommend gentamicin, in combination with other appropriate antimicrobial agents (typically ampicillin and clindamycin/metronidazole), for complicated, community-acquired intra-abdominal infections. Treat for 4 to 7 days.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours. Guidelines recommend gentamicin, in combination with other appropriate antimicrobial agents (typically ampicillin and clindamycin/metronidazole), for complicated, community-acquired intra-abdominal infections. Treat for 4 to 7 days.
-for the treatment of peritonitis in patients receiving peritoneal dialysis:
Intraperitoneal dosage*:
Infants, Children, and Adolescents: Intraperitoneal (IP) gentamicin can be administered continuously in each dialysate exchange bag with a loading dose of 8 mg/L initially and then a maintenance dose of 4 mg/L. Alternatively, for intermittent dosing, administer 0.6 mg/kg/dose IP for anuric patients and 0.75 mg/kg/dose IP for non-anuric patients once daily during the long-dwell periods. Treat for 2 to 3 weeks depending on infecting organism and the patient's clinical status.

For the treatment of complicated urinary tract infection (UTI), including pyelonephritis and catheter-associated urinary tract infection:
-for the treatment of complicated UTI, including pyelonephritis:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Infants 1 month: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. Infants younger than 2 to 3 months are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Infants, Children, and Adolescents 2 months to 17 years: 5 to 7.5 mg/kg/dose IV or IM every 24 hours. A study in pediatric patients age 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations. Treat for 24 to 48 hours or until patient is clinically stable and afebrile, followed by oral antibiotics for a total duration of 7 to 14 days.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours; however, this dosing does not account for gestational age or birthweight. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 12 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours. The FDA-approved dosage is 2.5 mg/kg/dose every 8 hours; however, this dosing does not account for gestational age or birthweight. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours. The FDA-approved dosage is 2.5 mg/kg/dose IV or IM every 8 hours; however, this dosing does not account for gestational age or birthweight. Neonates are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Infants 1 month: 2.5 mg/kg/dose IV or IM every 8 hours. Infants younger than 2 to 3 months are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Infants 2 to 11 months: 2.5 mg/kg/dose IV or IM every 8 hours. Treat for 24 to 48 hours or until patient is clinically stable and afebrile, followed by oral antibiotics for a total duration of 7 to 14 days.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours. Treat for 24 to 48 hours or until patient is clinically stable and afebrile, followed by oral antibiotics for a total duration of 7 to 14 days.
-for the treatment of catheter-associated UTI:
Intravenous or Intramuscular dosage (extended-interval dosing)*:
Infants 1 month: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for 7 to 14 days.
Infants, Children, and Adolescents 2 months to 17 years: 5 to 7.5 mg/kg/dose IV or IM every 24 hours for 7 to 14 days. A study in pediatric patients age 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Infants 1 month: 2.5 mg/kg/dose IV or IM every 8 hours. Infants younger than 2 to 3 months are at risk for systemic infection and rapid change in their clinical condition. Treat UTIs as presumed pyelonephritis in these patients.
Infants 2 to 11 months: 2.5 mg/kg/dose IV or IM every 8 hours.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours.

For the treatment of bone and joint infections, including osteomyelitis and infectious arthritis:
NOTE: Use lean body mass to calculate the gentamicin dose. Adjust dose based on serum gentamicin concentrations.
-for the treatment of osteomyelitis:
Intravenous dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV every 48 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV every 36 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV every 36 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants 1 to 2 months: 5 to 7.5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants, Children, and Adolescents 3 months to 17 years: 5 to 7.5 mg/kg/dose IV every 24 hours. One study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 3 to 4 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for severe or complicated infections.
Intravenous dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 to 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV every 18 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 to 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV every 12 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants 1 to 2 months: 2.5 mg/kg/dose IV every 8 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants 3 to 11 months: 2.5 mg/kg/dose IV every 8 hours. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 3 to 4 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for severe or complicated infections.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV every 8 hours. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 3 to 4 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for severe or complicated infections.
-for the treatment of infectious arthritis:
Intravenous dosage (extended-interval dosing)*:
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV every 48 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV every 36 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV every 36 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants 1 to 2 months: 5 to 7.5 mg/kg/dose IV every 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants, Children, and Adolescents 3 months to 17 years: 5 to 7.5 mg/kg/dose IV every 24 hours. One study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 months to younger than 2 years), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 2 to 3 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for septic hip arthritis or severe or complicated infections.
Intravenous dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 to 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 12 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV every 18 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 12 hours.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV every 12 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 to 24 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours; however, this dosing does not account for gestational age or birthweight.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV every 12 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV every 8 hours. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Premature infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV every 18 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections. The FDA-approved dosage is 2.5 mg/kg/dose IV every 8 hours; however, this dosing does not account for gestational age or birthweight.
Infants 1 to 2 months: 2.5 mg/kg/dose IV every 8 hours. Treat for 14 to 21 days or until clinically improved, followed by oral step-down therapy for a total duration of 4 to 6 weeks. A longer course (several months) may be needed for severe or complicated infections.
Infants 3 to 11 months: 2.5 mg/kg/dose IV every 8 hours. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 2 to 3 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for septic hip arthritis or severe or complicated infections.
Children and Adolescents: 2 to 2.5 mg/kg/dose IV every 8 hours. Treat for 2 to 4 days or until clinically improved, followed by oral step-down therapy for a total duration of 2 to 3 weeks for uncomplicated cases. A longer course (i.e., 4 to 6 weeks or longer) may be needed for septic hip arthritis or severe or complicated infections.

For postexposure plague prophylaxis*:
Intravenous or Intramuscular dosage:
Neonates 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours for 7 days as an alternative therapy.
Neonates 8 days and older: 5 mg/kg/dose IV or IM every 24 hours for 7 days as an alternative therapy.

For the treatment of invasive vibriosis*:
Intravenous or Intramuscular dosage (extended-interval dosing):
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours in combination with sulfamethoxazole; trimethoprim for 7 to 14 days.
Intravenous or Intramuscular dosage (conventional dosing):
Infants, Children, and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours in combination with sulfamethoxazole; trimethoprim for 7 to 14 days.

For the treatment of bronchiectasis*:
-for the treatment of acute exacerbations of bronchiectasis*:
Intravenous dosage (extended-interval dosing):
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV every 24 hours for 14 days as part of combination therapy.
-for the eradication of first or new isolates of Pseudomonas aeruginosa in patients with bronchiectasis*:
Intravenous dosage (extended-interval dosing):
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV every 24 hours for 14 days as part of combination therapy, followed by inhaled antibiotics for 4 to 12 weeks.
Respiratory (Inhalation) dosage (Solution for inhalation):
Children and Adolescents: 80 mg inhaled by nebulizer twice daily; may be used in combination with initial systemic therapy for 14 days; treat for 4 to 12 weeks following systemic therapy.
-for long-term treatment of bronchiectasis* to reduce exacerbations in patients with recurrent exacerbations:
Respiratory (Inhalation) dosage (Solution for inhalation):
Children and Adolescents: 80 mg nebulized every 12 hours based on limited data.

For the treatment of invasive listeriosis* with bacteremia as adjunct therapy:
NOTE: For CNS disease, see meningitis indication.
NOTE: Serum concentrations should be used to guide dosage adjustments. In most patients, dosage of aminoglycosides should be based on an estimate of lean body mass.
Intravenous or Intramuscular dosage (extended-interval dosing):
Neonates younger than 30 weeks gestation and 0 to 14 days: 5 mg/kg/dose IV or IM every 48 hours until clinical improvement for up to 14 days.
Neonates younger than 30 weeks gestation and 15 days and older: 5 mg/kg/dose IV or IM every 36 hours until clinical improvement for up to 14 days.
Neonates 30 to 34 weeks gestation and 0 to 10 days: 5 mg/kg/dose IV or IM every 36 hours until clinical improvement for up to 14 days.
Neonates 30 to 34 weeks gestation and 11 days and older: 5 mg/kg/dose IV or IM every 24 hours until clinical improvement for up to 14 days.
Neonates 35 weeks gestation and older and 0 to 7 days: 4 mg/kg/dose IV or IM every 24 hours until clinical improvement for up to 14 days.
Neonates 35 weeks gestation and older and 8 days and older: 5 mg/kg/dose IV or IM every 24 hours until clinical improvement for up to 14 days.
Infants, Children, and Adolescents: 5 to 7.5 mg/kg/dose IV or IM every 24 hours until clinical improvement for up to 14 days. A study in pediatric patients 3 months to 18 years (n = 114) suggested daily (i.e., every 24 hours) age-specific doses of 9.5 mg/kg/dose (3 to 23 months), 8.5 mg/kg/dose (2 to 7 years), and 7 mg/kg/dose (8 to 18 years) may be more appropriate to achieve goal gentamicin concentrations.
Intravenous or Intramuscular dosage (conventional dosing):
Neonates 0 to 7 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours until clinical improvement for up to 14 days.
Neonates 0 to 7 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 18 hours until clinical improvement for up to 14 days.
Neonates 0 to 7 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours until clinical improvement for up to 14 days. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Neonates 8 to 29 days weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 to 24 hours until clinical improvement for up to 14 days.
Neonates 8 to 29 days weighing 1.2 to 2 kg: 2.5 mg/kg/dose IV or IM every 12 hours until clinical improvement for up to 14 days.
Neonates 8 to 29 days weighing more than 2 kg: 2.5 mg/kg/dose IV or IM every 8 hours until clinical improvement for up to 14 days. Extend the interval to 18 to 24 hours for neonates on ECMO. Individualize subsequent dosing by monitoring serum drug concentrations. When ECMO is discontinued, dosage adjustment may be required.
Premature Infants 30 days and older weighing less than 1.2 kg: 2.5 mg/kg/dose IV or IM every 18 hours until clinical improvement for up to 14 days.
Infants, Children and Adolescents: 2 to 2.5 mg/kg/dose IV or IM every 8 hours until clinical improvement for up to 14 days.

Therapeutic Drug Monitoring:
Conventional Dosing
Usual target peak concentration: 5 to 10 mcg/mL depending on site of infection and pathogen
Usual target trough concentration: less than 2 mcg/mL; some experts recommend less than 1 mcg/mL for mild-moderate infections and patients at risk for renal toxicity

Extended-Interval Dosing (EID)
Neonates:
Usual target peak concentration: 5 to 12 mcg/mL depending on site of infection and pathogen
Usual target trough concentration: less than 2 mcg/mL

Nomogram for determining initial gentamicin dosing interval in Neonates 28 weeks gestation or younger:
The following recommendations are based on data from a retrospective study in 33 neonates 28 weeks gestation or younger (mean 25.8 weeks +/- 1.5 weeks) who received an EID regimen with a first dose of gentamicin 5 mg/kg/dose. A gentamicin serum concentration was obtained 22 hours after the initial dose. The dosing interval was 36 hours in 20 neonates and 48 hours in 13 neonates. Target peak (5 to 12 mcg/mL) and trough (less than 2 mcg/mL) concentrations were attained in more than 90% of neonates with this dosing nomogram.
Gentamicin Concentration 22 hours after the initial dose:
1.2 mcg/mL or less: Dosing interval of 24 hours
1.3 to 2.6 mcg/mL: Dosing interval of 36 hours
2.7 to 3.5 mcg/mL: Dosing interval of 48 hours
3.6 mcg/mL or more: Hold next dose, repeat concentration in 24 hours. Base dosing interval on time to achieve a concentration less than 2 mcg/mL.

Infants, Children, and Adolescents:
Usual target trough concentration: less than 1 mcg/mL
Optimal serum concentration monitoring has not been determined in pediatric patients; various methods have been developed and are often institution-specific. In general, the goal is to obtain a significant peak concentration, often in the range of 20 to 35 mcg/mL, and then allow sufficient time for the serum concentration to become undetectable. One method that has been used is to obtain 2 serum concentrations at least one half-life apart (e.g., 2 and 6 hours after the dose) and use those concentrations to calculate a peak and trough and ensure that the serum concentration is not undetectable for significantly longer than the estimated post-antibiotic effect (e.g., 4 to 7 hours). Once an extended interval dose has been determined to be appropriate by measuring serum concentrations, follow-up concentrations are often trough-only to ensure no accumulation is occurring.

General Therapeutic Drug Monitoring Information
-The importance of achieving peak concentrations in several-fold excess of the organism's MIC has been established. Both time-kill studies, as well as studies in humans, have shown that a peak:MIC ratio of more than 8 to 12:1 is associated with successful regimens for systemic infections. Consideration must also be given to the site of infection as antimicrobial tissue penetration is also a factor. These data have led to the development of extended interval aminoglycoside therapy (often referred to as 'once daily dosing'), with a high dose of gentamicin given to achieve the peak:MIC goals. In adults, with 7 mg/kg/day dosing, peak concentrations often reach 20 mcg/mL to maintain a serum peak:MIC ratio of 10 for organisms with MICs of 2 mcg/mL.
-Because elevated serum trough concentrations are associated with an increased risk of toxicity, trough values for conventional dosing should fall below 2 mcg/mL, and trough values for extended-interval dosing are designed to fall below the MIC for an extended period and are often undetectable. The post-antibiotic effect (PAE) of aminoglycosides against gram-negative organisms is also used to justify the low trough concentrations..
-For gram-positive infective endocarditis, when daily dosage (3 to 6 mg/kg/day) is divided every 8 hours, it is recommended to adjust the gentamicin dose to maintain peak serum concentrations of 3 to 4 mcg/mL and trough concentrations of less than 1 mcg/mL. Gentamicin is only synergistic, and there is limited PAE for aminoglycosides with gram-positive organisms.
-For patients with bacterial meningitis/shunt infection receiving intraventricular gentamicin, a goal concentration of 5 to 10 times the MIC or a CSF bactericidal titer of 1:8 or more is desired.
-Most urinary tract infections may be adequately treated with lower peak serum concentrations as aminoglycosides are mainly renally eliminated; therefore, drug accumulation in the urine is higher than in the serum.

Maximum Dosage Limits:
-Neonates
Aminoglycoside dosing is highly variable and dependent on several factors. 7.5 mg/kg/day IV/IM is FDA-approved maximum; however, this dose is not typically used in clinical practice. Usual maximum doses in neonates are as follows:
Younger than 30 weeks gestation: 5 mg/kg/dose IV/IM every 36 to 48 hours.
30 to 34 weeks gestation: 5 mg/kg/dose IV/IM every 24 to 36 hours.
35 weeks gestation and older: 4 to 5 mg/kg/dose IV/IM every 24 hours.
-Infants
Aminoglycoside dosing is highly variable and dependent on several factors. 7.5 mg/kg/day IV/IM is FDA-approved maximum. There is no maximum dose stated for ophthalmic administration. Safety and efficacy of topical administration have not been established.
-Children
Aminoglycoside dosing is highly variable and dependent on several factors. 7.5 mg/kg/day IV/IM is FDA-approved maximum. There is no maximum dose stated for ophthalmic or topical administration.
-Adolescents
Aminoglycoside dosing is highly variable and dependent on several factors. 7.5 mg/kg/day IV/IM is FDA-approved maximum. There is no maximum dose stated for ophthalmic or topical administration.

Patients with Hepatic Impairment Dosing
Gentamicin does not undergo hepatic metabolism. Specific guidelines for dosage adjustment in hepatic impairment are not available; it appears that no dosage adjustments are needed.

Patients with Renal Impairment Dosing
Conventional Dosing
The following dosage adjustments are recommendations based on a usual dose of 2.5 mg/kg/dose IV every 8 hours.
GFR more than 50 mL/minute/1.73 m2: No initial adjustment; monitor serum concentrations.
GFR 30 to 50 mL/minute/1.73 m2: 2.5 mg/kg/dose IV/IM every 12 to 18 hours; monitor serum concentrations.
GFR 10 to 29 mL/minute/1.73 m2: 2.5 mg/kg/dose IV/IM every 18 to 24 hours; monitor serum concentrations.
GFR less than 10 mL/minute/1.73 m2: 2.5 mg/kg/dose IV/IM every 48 to 72 hours; monitor serum concentrations.

Extended-Interval Dosing
Give a single dose and monitor serum concentrations. If significant impairment is present, consider reducing the initial dose and then evaluate serum concentrations.

Intermittent hemodialysis
The FDA-approved product labeling recommends 2 mg/kg/dose IV or IM after the initial hemodialysis session. Subsequent doses should be guided by serum gentamicin concentrations. Factors such as patient size, site of infection, and organism susceptibility should also be considered.

Continuous ambulatory peritoneal dialysis (CAPD)
For peritonitis, the International Society for Peritoneal Dialysis (ISPD) states that intraperitoneal (IP) gentamicin can be administered continuously in each dialysate exchange bag with a loading dose of 8 mg/L and a maintenance dose of 4 mg/L. For intermittent dosing, administer 0.6 mg/kg/dose IP for anuric patients and 0.75 mg/kg/dose IP for non-anuric patients once daily during the long-dwell periods.

Continuous Renal Replacement Therapy (CRRT)
2 to 2.5 mg/kg/dose IV/IM every 12 to 24 hours; monitor serum concentrations.

*non-FDA-approved indication

Monograph content under development

Mechanism of Action: Gentamicin is bactericidal in action. Similar to other aminoglycosides, it works by inhibiting bacterial protein synthesis through irreversible binding to the 30 S ribosomal subunit of susceptible bacteria. Gentamicin is actively transported into the bacterial cell where it binds to receptors present on the 30 S ribosomal subunit. This binding interferes with messenger RNA (mRNA). As a result, abnormal, nonfunctional proteins are formed due to misreading of the bacterial DNA. Eventually, susceptible bacteria die because of the lack of functional proteins. One aspect essential to aminoglycoside lethality is the need to achieve intracellular concentrations in excess of extracellular. Anaerobic bacteria are not susceptible to aminoglycosides due, at least in part, to a lack of an active transport mechanism for aminoglycoside uptake. The uptake of aminoglycosides may be facilitated by the presence of inhibitors of the bacterial cell wall (i.e., beta-lactams, vancomycin).

Against gram-negative aerobic rods, aminoglycosides exhibit 'concentration-dependent killing' and a 'post-antibiotic effect' (PAE). 'Concentration-dependent killing' describes the principle that bactericidal effects increase as the concentration increases. PAE is where suppression of bacterial growth continues after the antibiotic concentration falls below the bacterial MIC. The post-antibiotic effect can be bacteria-specific, as well as drug-specific. The PAE of aminoglycosides is short for most gram-positive organisms (less than 2 hours) and longer for gram-negative organisms (2 to 8 hours), such as E. coli, K. pneumoniae, and P. aeruginosa. Both of these phenomena are being exploited in designing dosage regimens that employ higher doses administered at longer intervals. The major pharmacodynamic parameters that determine efficacy of aminoglycosides are the serum peak concentration to MIC ratio (peak/MIC) and the AUC to MIC ratio (AUC/MIC). Both time-kill studies as well as studies in humans have shown that a peak/MIC of more than 8 to 12/1 is associated with successful regimens. An AUC/MIC ratio of more than 125 has also been associated with a successful regimen.

The mechanism of renal toxicity with aminoglycosides is associated with accumulation of aminoglycosides in the renal tubule, which is a saturable process. Elevated serum trough concentrations are associated with an increased risk of toxicity.

The mechanism of ototoxicity relates to the aminoglycoside-induced destruction of sensory hair cells of the inner ear. The cochlear sensory cells that are most vulnerable are in the basal end, thereby leading to high-frequency hearing loss first. As ototoxicity ascends toward the apex of the cochlea, the lower frequencies are affected. Sensory cells that deal with vestibular function may also be affected. Aminoglycosides may cause free-radical damage to sensory cells and neurons. Biochemically, aminoglycosides may bind to polyphosphoinositides, which are part of the transmembrane signaling system mediating physiological effects of hormones, neurotransmitters, and neuromodulators which may interfere with essential mechanisms of cell physiology. Neural destruction without any cochlear hair cell damage has also been described. There may also be a genetic mitochondrial RNA mutation that may predispose some patients to aminoglycoside ototoxicity. Aminoglycosides enter the inner ear rapidly, but it is suggested that aminoglycoside concentrations do not correlate with the development of ototoxicity. Likely, the aminoglycoside concentrations in the inner ear dissipate slowly, which is consistent with the possibility of developing ototoxicity days to weeks after drug discontinuation.

The susceptibility interpretive criteria for gentamicin are delineated by pathogen. The MICs are defined for Staphylococcus sp. as susceptible at 4 mcg/mL or less, intermediate at 8 mcg/mL, and resistant at 16 mcg/mL or more (only to be used in combination with other active agents). The MICs are defined for P. aeruginosa, Acinetobacter sp., non-Enterobacterales, Y. pestis, Corynebacterium sp. and related Coryneform genera, Bacillus sp. (excluding B. anthracis) and related genera, Aeromonas sp., and Vibrio sp. as susceptible at 4 mcg/mL or less, intermediate at 8 mcg/mL, and resistant at 16 mcg/mL or more. The Clinical and Laboratory Standards Institute (CLSI) and the FDA differ on MIC interpretation for Enterobacterales (excluding Salmonella sp. and Shigella sp.). The MICs are defined for Enterobacterales by the FDA as susceptible at 4 mcg/mL or less, intermediate at 8 mcg/mL, and resistant at 16 mcg/mL or more; however, the MICs are defined for Enterobacterales by the CLSI as susceptible at 2 mcg/mL or less, intermediate at 4 mcg/mL, and resistant at 8 mcg/mL or more (based on a dosage regimen of 7 mg/kg every 24 hours). The MICs are defined for F. tularensis and Brucella sp. as susceptible at 4 mcg/mL or less. However, based on the pharmacodynamic properties of aminoglycosides, an MIC of 2 mcg/mL or more would likely lead to unacceptably low probabilities of good clinical outcomes when using reasonable dosage regimens.

Aminoglycoside resistance is well documented. There are a variety of resistance mechanisms employed by different pathogens. Enzymatic inhibition by gram-negative pathogens and Enterococcus sp. via aminoglycoside-modifying enzymes is achieved by modification of the aminoglycoside as it is transported across the cytoplasmic membrane. Alterations in the inner membrane porin channels by Pseudomonas aeruginosa decrease antimicrobial penetration to the site of activity within the bacterial cell. Some gram-negative organisms and Enterococcus sp. can alter the ribosomal target sites of the aminoglycosides to decrease binding, thereby decreasing antimicrobial activity. Aminoglycosides can also be actively transported out of the bacterial cells via efflux pumps.

Pharmacokinetics: Gentamicin is administered intravenously, intramuscularly, topically, and via the ophthalmic route. Gentamicin distributes into extracellular fluid. Volume of distribution approximates extracellular space; therefore, peak serum concentrations may be lower in patients with a large volume of extracellular fluid. Protein binding of gentamicin is low (0% to 30%). Gentamicin can be detected in the serum, lymph, tissues, sputum, synovial fluid, and peritoneal fluid. Concentrations in the renal cortex may be 8 times higher than in the serum. Gentamicin crosses the peritoneal wall and the placental membranes. There is poor diffusion into the subarachnoid space with systemic administration; therefore, concentrations in the cerebrospinal fluid are often low and dependent upon dose, rate of penetration, and degree of meningeal inflammation. There is minimal penetration into ocular tissues after systemic administration.

Gentamicin is not metabolized. Approximately >= 70% of the gentamicin dose is recovered in the urine after 24 hours. Minimal amounts are excreted into bile. Elimination is almost exclusively via glomerular filtration. Reabsorption of a small amount of the drug by the proximal tubule results in accumulation in the renal cortex, which may be responsible for nephrotoxicity. Renal clearance of gentamicin is similar to endogenous creatinine. The endogenous creatinine clearance rate and serum creatinine concentration have a high correlation with the half-life of gentamicin; gentamicin elimination half-life varies according to renal function. Febrile states may be associated with decreased serum concentrations and a shorter half-life. In severely burned patients, the half-life may also be decreased. In children with normal renal function, the serum half-life is approximately 1.2 to 2 hours; however, there is considerable interpatient variation.

Affected cytochrome P450 isoenzymes: none


-Route-Specific Pharmacokinetics
Intravenous Route
After IV administration, there is an acute distribution phase, followed by a linear elimination phase. "Peak" concentration that is post-distributional, is achieved approximately 30 minutes after IV administration.

Intramuscular Route
Peak concentration is achieved approximately 30 to 60 minutes after IM administration. Elimination half-life is longer after IM administration. In 1 pharmacokinetic study, elimination half-life was prolonged by approximately 29 minutes after IM administration. In general, IM administration of antibiotics in very low birth weight neonates is not practical due to small muscle mass and unreliable absorption.


-Special Populations
Pediatrics
Neonates
Pharmacokinetics are highly variable in neonates, with factors such as renal maturation and postmenstrual age playing a significant role. Neonates have a larger volume of distribution (Vd) and a reduced clearance compared with children and adults. In an analysis of pharmacokinetic studies of gentamicin in neonates with varying gestational ages and postnatal days, the Vd ranged from 0.45 to 0.75 L/kg, clearance ranged from 0.53 to 1.72 mL/kg/minute, and elimination half-life ranged from approximately 5 to 14 hours. Clearance increases with increasing gestational age. Clearance averages 0.83 mL/kg/minute in neonates with a gestational age of 27 weeks and increases to 3.3 mL/kg/minute in neonates with a gestational age of 40 weeks. The elimination half-life in neonates < 32 weeks gestational age is approximately 9 to 14 hours and decreases to approximately 5 to 8 hours in neonates >= 36 weeks gestational age.

Neonates Receiving Extracorporeal Membrane Oxygenation (ECMO)
Treatment with ECMO results in a larger volume of distribution (Vd) and slower clearance compared to those of infants not receiving ECMO. Pharmacokinetic parameters may change frequently due to many contributing factors (e.g., critical condition of the patient, changes in renal function or addition of renal replacement therapy, timing of circuit changes, etc.); careful monitoring is required. Vd and half-life typically begin to trend back towards more typical values after decannulation.

Neonates with Hypoxic Ischemic Encephalopathy (HIE) Receiving Hypothermia
Pharmacokinetic data based on Monte Carlo simulations from 29 term neonates with HIE receiving hypothermia showed that these patients have a 25% to 50% lower gentamicin clearance compared to normothermic, nonasphyxiated neonates.

Children and Adolescents
Volume of distribution (Vd) is approximately 0.25 L/kg in children and adolescents. In children with normal renal function, the serum half-life is approximately 1.2 to 2 hours; however, there is considerable interpatient variation.

Renal Impairment
In patients with renal impairment, the clearance of gentamicin is significantly decreased and the elimination half-life is substantially increased. The change in clearance is proportional to the degree of renal impairment.