Loratadine is an oral non-sedating antihistamine (H1-blocker) that is similar in structure to cyproheptadine and azatadine. Due to poor penetration into the central nervous system (CNS) and a low affinity for CNS histamine H1-receptors, the drug is less likely to cause sedation or other CNS effects compared with traditional, sedating antihistamines. Unlike astemizole and terfenadine, which are no longer marketed due to arrhythmia risks, loratadine has not been associated with QT prolongation. Loratadine is used in both adult and pediatric populations for allergic rhinitis and chronic spontaneous urticaria or other allergic symptoms. Loratadine was first approved by the FDA in April 1993 as a prescription medication. Loratadine products became approved for non-prescription (OTC) sale in December 2002.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Oral Administration
-Loratadine may be administered without regard to meals.
Oral Solid Formulations:
-Rapidly-disintegrating oral tablets (e.g., Alavert orally disintegrating tablets or Claritin Reditabs): Place on tongue; allow to dissolve and then swallow. May be administered with or without water. Store in a dry place at controlled room temperature. Use within 6 months of opening laminated foil pouch, and immediately upon opening an individual tablet blister.
Oral Liquid Formulations:
-Oral syrup, suspension, or solution (1 mg/ml): Measure dosage using a calibrated measuring device. Suspension formulations may not need to be shaken; check labeling.
Similar to other low-sedating antihistamines, side effects from loratadine reported in placebo-controlled trials in adults and children aged 12 years and older include headache (12% vs. 11% placebo), somnolence/drowsiness (8%, vs. 6% placebo) and fatigue (4%, vs. 3% placebo). Dizziness, hypoesthesia, hyperhidrosis, tremor, vertigo, asthenia, dysphonia, hypertonia, malaise, migraine, muscle cramps (legs), paresthesias, arthralgia, and myalgia have been reported in at least one adult or pediatric patient receiving loratadine during clinical trials. Nervousness (4% vs. 2% placebo), dysphonia (2% vs. <1% placebo), fatigue (3% vs. 2% placebo), malaise (2% vs. 0% placebo) and hyperkinesis (3% vs. 1% placebo) have been reported in placebo-controlled trials in children 6 to 12 years old. Fatigue also occurred in 2% to 3% of young children (2 to 5 years old) treated with loratadine during the placebo-controlled trial. Seizures have been reported rarely during post-marketing experience (patient ages unspecified). Patients should be warned about undertaking hazardous tasks while taking loratadine, although the risk of sedation is relatively low.
Diarrhea (2% to 3%) and abdominal pain (2% vs. 0% placebo) have been reported in children 2 to 5 years and 6 to 12 years of age, respectively, receiving loratadine during placebo-controlled clinical trials. In addition, dysgeusia, anorexia, constipation, diarrhea, dyspepsia, flatulence, gastritis, hiccups, appetite stimulation, loose stools, weight gain, polydipsia, nausea, and vomiting have been reported in at least one adult or pediatric patient receiving loratadine during clinical trials.
Cardiovascular adverse events may occur during loratadine therapy. Hypertension, hypotension, palpitations, supraventricular tachycardia (SVT), syncope, sinus tachycardia, and chest pain (unspecified) have been reported in at least one adult or pediatric patient receiving loratadine during clinical trials. Peripheral edema has been reported during post-marketing experience. Palpitations have been reported in children with overdoses of greater than 10 mg of loratadine. In a human study in which doses 4 times the clinical dose were administered to adults for up to 90 days, loratadine did not cause clinically significant changes on the QT interval. The manufacturer reports that in a single, rising-dose study in which doses up to 160 mg (16 times the clinical dose) were studied in adults, loratadine did not cause any clinically significant changes on the QTc interval.
Xerostomia (3% vs. 2% placebo) was reported in adult and pediatric patients 12 years and older during clinical trials of loratadine. Pharyngitis, epistaxis, otalgia, stomatitis, influenza-like symptoms, and tooth disorder were reported in 2% to 3% of young children 2 to 5 years of age receiving loratadine during clinical trials. Wheezing (4% vs. 2% placebo) was reported in children 6 to 12 years of age. Adverse effects of the mouth, nose, and throat including altered salivation, bronchitis, bronchospasm, dyspnea, hemoptysis, laryngitis, nasal dryness, sinusitis, otalgia, and tinnitus were reported in at least one adult or pediatric patient receiving loratadine during clinical trials.
Viral infection (2% to 3%) and upper respiratory infection (2% vs. < 1% placebo) have been reported in children 2 to 5 years and 6 to 12 years, respectively, during loratadine clinical trials. Cough, chills, fever, and sneezing were reported in at least one adult or pediatric patient receiving loratadine during clinical trials.
Amnesia, anxiety, confusion, depression, impaired concentration, insomnia, irritability, paranoia, and libido decrease have been reported in at least one adult or pediatric patient in loratadine clinical trials.
Reproductive organ adverse effects including mastalgia, dysmenorrhea, menorrhagia, vaginitis, and impotence (erectile dysfunction) were reported in at least one adult or pediatric patient in loratadine clinical trials. In addition, breast enlargement has been reported during post-marketing experience.
Hypersensitivity reactions including anaphylaxis/anaphylactoid reactions, erythema multiforme, and alopecia have been rarely reported with post-marketing loratadine use. During clinical trials, rash (unspecified) was reported in 2% to 3% of children 2 to 5 years of age. Hypersensitivity or dermatologic reactions reported in at least one adult or pediatric patient during clinical trials include angioedema/angioneurotic edema, dermatitis, dry hair, xerosis, flushing, photosensitivity, pruritus, purpura, and urticaria.
Altered micturition, urine discoloration, urinary incontinence, and urinary retention have been reported in at least one adult or pediatric patient in loratadine clinical trials.
Abnormal hepatic function including elevated hepatic enzymes, jaundice, hepatitis, and hepatic necrosis have been reported during post-marketing experience with loratadine.
Thrombocytopenia has been reported rarely during post-marketing experience with loratadine.
Conjunctivitis (2% vs. < 1% placebo) was reported in pediatric patients 6 to 12 years of age during clinical trials for loratadine. Altered lacrimation, blurred vision, ocular pain, and blepharospasm have been reported in at least one adult or pediatric patient receiving loratadine during clinical trials.
Loratadine is contraindicated in any individual hypersensitive to the drug or any of the ingredients of the specific drug formulation, or in any patient hypersensitive to desloratadine, due to cross-sensitivity.
Use antihistamines with caution in patients with asthma. The anticholinergic activity of H1-antagonists may result in thickened bronchial secretions in the respiratory tract thereby aggravating an acute asthmatic attack. However, these anticholinergic effects do not preclude the use of H1-antagonists in all asthmatic patients, particularly if the above respiratory symptom is not a primary component of the illness. Because loratadine possesses only weak anticholinergic properties, it would not be expected to adversely affect the respiratory status of most asthmatic patients.
Some formulations of loratadine (e.g., Alavert Orally Disintegrating tablets, Dimetapp ND Orally Disintegrating tablets) contain phenylalanine. These products should be used cautiously in patients with phenylketonuria.
Loratadine is generally non-sedating. However, the drug may cause drowsiness or somnolence in individual patients; therefore patients receiving this medication should be advised to use caution in performing activities requiring coordination and concentration, such as driving or operating machinery until the effects of the drug are known.
Loratadine is extensively metabolized in the liver. Loratadine should be used cautiously in those with hepatic disease and initial dosage adjustments should be made according to the manufacturer's guidelines.
Loratadine should be used cautiously in those with renal failure or renal impairment. The exposure and maximal concentrations of loratadine and its metabolite are elevated in the presence of significant renal impairment (CrCl less than 30 mL/min). Initial dosage adjustments should be made according to the manufacturer's guidelines based on patient age.
No teratogenic or mutagenic effects were observed in animal studies of loratadine use during pregnancy. Pregnant patients should see their health care professional for a proper diagnosis and for treatment recommendations. Loratadine and cetirizine are acceptable antihistamine alternatives based on their excellent safety data and recommendation in multiple guidelines for use during pregnancy.
Loratadine and its metabolite, desloratadine, are excreted into breast milk; breast-feeding women are advised to consult a healthcare professional prior to using loratadine. In one study, a single loratadine dose of 40 mg (4 times the usual dose) was administered to 6 lactating women. Average loratadine peak milk concentrations, 2 hours after administration, were 29.2 mcg/L (range 20.4 to 39 mcg/L); average desloratadine peak milk concentrations, 5.3 hours after loratadine administration, were 16 mcg/L (range 9 to 29.6 mcg/L). The total amount excreted in milk over 48 hours was 11.7 mcg of loratadine and desloratadine. The calculated average and maximum expected exposures of loratadine and desloratadine in milk were 0.46% and 1.1% of the maternal weight-adjusted dose, respectively, after the 40 mg dose. Approximately 3 mcg would be expected to be excreted in the milk with a 10 mg dose. Because of its lack of sedation and low milk concentrations, maternal use would not be expected to cause adverse effects in breast-fed babies and loratadine is considered usually compatible with breast-feeding. The British Society for Allergy and Clinical Immunology also recommends loratadine at the lowest dose as a preferred antihistamine in breast-feeding women. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.
Safety and efficacy have not been established for loratadine use in neonates, infants, or children less than 2 years of age. Antihistamines generally should not be used in neonates due to the possibility of paradoxical CNS stimulation or seizures.
For the management of symptoms of seasonal allergies or perennial allergies, including allergic rhinitis:
Oral dosage (tablets or capsules):
Adults: 10 mg PO once daily. Do not exceed 10 mg/day.
Children and Adolescents 6 to 17 years: 10 mg PO once daily. Do not exceed 10 mg/day.
Oral dosage (orally disintegrating tablets):
Adults: 5 mg PO twice daily or 10 mg PO once daily. Do not exceed 10 mg/day.
Children and Adolescents 6 to 17 years: 5 mg PO twice daily or 10 mg PO once daily. Do not exceed 10 mg/day.
Oral dosage (chewable tablets, OTC product):
Adults: 10 mg PO once daily. Do not exceed 10 mg/day.
Children and Adolescents 6 to 17 years: 10 mg PO once daily. Do not exceed 10 mg/day.
Children 2 to 5 years: 5 mg PO once daily. Do not exceed 5 mg/day.
Oral dosage (oral syrup or solution):
Adults: 10 mg PO once daily. Do not to exceed 10 mg/day.
Children and Adolescents 6 to 17 years: 10 mg PO once daily. Do not to exceed 10 mg/day.
Children 2 to 5 years: 5 mg PO once daily. Do not to exceed 5 mg/day.
For adjunctive exercise-induced bronchospasm prophylaxis* in patients with allergies:
Oral dosage:
Adults, Adolescents, and Children 7 years of age and older: 10 mg PO once daily has been used. Because allergy control can lead to better asthma control, the American Thoracic Society recommends daily antihistamine therapy in patients with EIB and allergies who continue to have symptoms despite using an inhaled short-acting beta-2 agonist (SABA) before exercise, or in those who require daily (or more frequent) SABA use. Antihistamines should not be used in nonallergic patients with EIB. Available studies demonstrate some reduction in the symptoms of exercise-induced bronchospasm (EIB). Loratadine 10 mg/day significantly reduced the decrease from baseline in FEV-1 following exercise in a randomized, double-blind, placebo controlled trial in asthmatic patients aged 7 to 17 years with allergies.
For the management of symptoms of chronic spontaneous urticaria (e.g., relief of pruritus, reduction in the size and number of hives):
Oral dosage (tablets or capsules):
Adults: 10 mg PO once daily. Do not exceed 10 mg in 24 hours.
Children and Adolescents 6 to 17 years: 10 mg PO once daily. Do not exceed 10 mg in 24 hours.
Oral dosage (orally disintegrating tablets):
Adults, Adolescents, and Children 6 years and older: 10 mg/day PO, given as 5 mg PO twice daily or 10 mg once daily. Tablet disintegrates with or without water. Do not exceed 10 mg in 24 hours.
Oral dosage (chewable tablets):
Adults, Adolescents, and Children 6 years and older: 10 mg PO daily. Do not exceed 10 mg in 24 hours.
Children 2 to 5 years: 5 mg PO daily. Do not exceed 5 mg in 24 hours.
Oral dosage (oral syrup or solution):
Adults, Adolescents, and Children 6 years and older: 10 mg PO daily. Do not to exceed 10 mg in 24 hours.
Children 2 to 5 years: 5 mg PO once daily. Do not to exceed 5 mg in 24 hours.
Maximum Dosage Limits:
NOTE: Do not exceed recommended dosage limits for the specific product prescribed; the following are general guidelines:
-Adults
10 mg/day PO.
-Geriatric
10 mg/day PO.
-Adolescents
10 mg/day PO.
-Children
6 to 12 years: 10 mg/day PO.
2 to 5 years: 5 mg/day PO.
1 year: Safety and efficacy have not been established.
Patients with Hepatic Impairment Dosing
For adults and children 6 years and older: Reduce initial dosage to 10 mg PO every other day.
For children 2 to 5 years: Reduce initial dose to 5 mg PO every other day.
Patients with Renal Impairment Dosing
CrCl 30 mL/minute or greater: No dosage adjustment needed.
CrCl less than 30 mL/minute: For adults and pediatric patients 6 years and older, reduce initial dosage to 10 mg PO every other day. For children 2 to 5 years, reduce initial dose to 5 mg PO every other day.
Intermittent hemodialysis
Loratadine and its active metabolite are not removed by hemodialysis. See dosage for patients with CrCl less than 30 mL/min.
*non-FDA-approved indication
Acetaminophen; Aspirin; Diphenhydramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Caffeine; Pyrilamine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Dextromethorphan; Doxylamine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Diphenhydramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Pamabrom; Pyrilamine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Acrivastine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Brompheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Dextromethorphan; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Pseudoephedrine; Dextromethorphan: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Carbinoxamine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Cetirizine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Cetirizine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlophedianol; Dexbrompheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorcyclizine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Codeine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Hydrocodone: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Clemastine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Cyproheptadine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Desloratadine: (Major) Desloratadine is the active metabolite of Loratadine. These 2 drugs should not be given at the same time due to the duplication of therapy and the resultant increase in desloratadine concentrations, which may lead to increased CNS or anticholinergic effects.
Desloratadine; Pseudoephedrine: (Major) Desloratadine is the active metabolite of Loratadine. These 2 drugs should not be given at the same time due to the duplication of therapy and the resultant increase in desloratadine concentrations, which may lead to increased CNS or anticholinergic effects.
Dexbrompheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Dexbrompheniramine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Dexchlorpheniramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Dimenhydrinate: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Diphenhydramine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Ibuprofen: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Naproxen: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Phenylephrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Doxylamine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Doxylamine; Pyridoxine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Fexofenadine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Fexofenadine; Pseudoephedrine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Heparin: (Minor) Antihistamines may partially counteract the anticoagulant actions of heparin, according to the product labels. However, this interaction is not likely of clinical significance since heparin therapy is adjusted to the partial thromboplastin time (aPTT) and other clinical parameters of the patient.
Hydroxyzine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Levocetirizine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Meclizine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Pseudoephedrine; Triprolidine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Sedating H1-blockers: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Sincalide: (Moderate) Sincalide-induced gallbladder ejection fraction may be affected by concurrent medications, including H1-blockers. False study results are possible; thorough patient history is important in the interpretation of procedure results.
Triprolidine: (Minor) Although loratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of loratadine with CNS depressants such as other H1-blockers.
Loratadine is highly selective for histamine H1-receptors. Unlike cromolyn and nedocromil which block histamine release, H1-antagonists compete with free histamine for binding at H1-receptor sites. This competitive antagonism blocks the effects of histamine on H1-receptors in the GI tract, uterus, large blood vessels, and bronchial muscle. Loratadine does not readily cross the blood-brain barrier, and it preferentially binds at H1-receptors in the periphery rather than within the brain, which probably accounts for some of its nonsedating character. H1-blockers are similar in structure to anticholinergics, local anesthetics, antispasmodics, and ganglionic- and adrenergic-blocking agents, sharing some of their properties. H1-blockers possess anticholinergic properties in varying degrees; however, loratadine does not exert significant anticholinergic effects at therapeutic concentrations. In vitro studies have shown that loratadine has a weak affinity for acetylcholine and alpha-adrenergic receptors.
Loratadine is administered orally. It is 97% protein-bound and is excreted into breast milk. Loratadine has a high first pass effect and is almost completely metabolized in the liver to the minimally active metabolite, descarboethoxyloratadine. In vitro studies indicate that metabolism to descarboethoxyloratadine predominantly by CYP3A4 and, to a lesser extent, by cytochrome CYP2D6. In the presence of a CYP3A4 inhibitor, loratadine is metabolized to descarboethoxyloratadine predominantly by CYP2D6. The normal mean elimination half-lives of loratadine and its metabolite are 8.4 hours (range 3 to 20 hours) and 28 hours, respectively. Elimination occurs through the fecal and renal routes.
Affected cytochrome P450 (CYP450) isoenzymes and drug transporters: CYP3A4, CYP2D6, P-gp
Metabolism of loratadine occurs predominantly by CYP3A4 and, to a lesser extent, by cytochrome CYP2D6. Concurrent administration with either ketoconazole, erythromycin (both CYP3A4 inhibitors), or cimetidine (CYP2D6 and CYP3A4 inhibitor) to healthy volunteers was associated with increased plasma concentrations of loratadine. However, in drug-drug interaction studies there were no clinically relevant changes in the safety profile of loratadine associated with these increases. Loratadine is also a substrate for P-glycoprotein (P-gp) transport; however, no clinically significant drug-drug interactions have been reported with P-gp inhibitors.
-Route-Specific Pharmacokinetics
Oral Route
After oral administration, the onset of action of loratadine occurs within 1 to 3 hours, with peak effects in 8 to 12 hours and a duration of action greater than 24 hours. Administration with food increases absorption and AUC up to 40% for the syrup or tablets and up to 48% for the rapidly-disintegrating tablets. The time to peak concentrations (Tmax) is delayed by administration with food. However, since the clinical response is unaffected, the drug can be administered without regard to meals.
-Special Populations
Hepatic Impairment
Loratadine dosages should be altered in patients with hepatic impairment. Patients with chronic alcoholic liver disease achieve peak serum concentrations which are approximately double those observed in normal controls. Those with chronic alcoholic liver disease exhibited prolonged elimination half lives for both the parent drug (24 hours) and its metabolite (37 hours), and these increased with the severity of the hepatic impairment. Dosing adjustments are recommended based on the changes in these parameters.
Renal Impairment
Loratadine dosages should be reduced in patients with renal impairment (CrCl less than 30 mL/minute). Peak serum concentrations of loratadine may increase up to 73% in the presence of severe renal impairment; although elimination half-lives are similar to those of normal controls. Hemodialysis does not alter the pharmacokinetics of loratadine or its metabolite.
Pediatrics
Children 6 to 12 years
The pharmacokinetic profile of loratadine in children ages 6 to 12 years is similar to that of adults. The pharmacokinetic parameters (AUC and Cmax) of 13 children (aged 8 to 12 years) receiving a single-dose of 10 mg loratadine syrup were comparable to those following administration of a 10 mg tablet or syrup to adult volunteers.
Children 2 to 5 years
The pharmacokinetic profile of loratadine in children (2 to 5 years of age) is similar to that of adults. The pharmacokinetic parameters (AUC and Cmax) of 18 children (aged 2 to 5 years) receiving a single-dose of 5 mg loratadine syrup were comparable to those after administration of a 10 mg tablet or syrup to adult volunteers or children 8 years of age and older.
Geriatric
In elderly subjects, the AUC and peak plasma concentrations of loratadine are roughly 50% greater than those observed in young adults. The elderly have prolonged elimination half lives for both the parent drug (18.2 hours) and its metabolite (17.5 hours). However, no dosage adjustments in the elderly are considered necessary based on age alone.