Silver nitrate is a topical cauterizing agent. Treatment with this medicine produces astringent, germicidal, and epithelial stimulant actions. Silver nitrate is used topically for the treatment of helomas. Silver nitrate was initially marketed for use before 1962, which is when Congress passed the amended Federal Food, Drug, and Cosmetic Act requiring that the FDA establish both safety and efficacy for all subsequently approved drugs. Silver nitrate is an unapproved marketed drug that has not been formally evaluated by the FDA.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Topical Administration
-Silver nitrate is for external use only.
-Do not apply to wounds, cuts, broken skin, or eyes.
-Treat for 2 to 3 weeks as needed.
Other Topical Formulations
Solution Formulation
-Moisten a cotton applicator by dipping into the solution.
-Using the moistened cotton applicator, apply solution to affected area 2 to 3-times per week.
Prolonged or frequent use of sliver nitrate may result in permanent skin discoloration.
Silver nitrate is only indicated for topical administration; exposing the eyes to silver nitrate may result in ocular irritation. The degree of irritation depends on the concentration of silver nitrate and the length of exposure. Symptoms may include ocular pain, burning, tearing, and redness.
Silver nitrate is only to be administered topically; avoid administering silver nitrate via the oral route. Ingesting silver nitrate may result in abdominal pain, burning sensation in the throat, vomiting, gastroenteritis, and death.
Skin irritation, such as burning and erythema, may occur following topical administration of silver nitrate. The irritation severity depends on the silver nitrate concentration and the length of exposure.
Silver nitrate is indicated for topical treatment of intact skin; take measures to avoid accidental exposure to silver nitrate. Ingestion of silver nitrate may result in burning throat, abdominal pain, vomiting, and severe gastroenteritis resulting in death. If accidental ingestion occurs, do not induce vomiting. Eye irritation may result from ophthalmic contact with silver nitrate; the degree of irritation depends on the period of contact and the concentration of the silver nitrate. If ocular exposure occurs, the eyes should be washed out for a period of 15 minutes with lukewarm water. Do not use silver nitrate on broken skin such as a wound or skin abrasion. Non-intact skin exposed to silver nitrate should be washed thoroughly with soap and water. Instruct all patients to seek immediate medical attention if accidentally exposed to silver nitrate.
Safety and efficacy of silver nitrate products have not been established in neonates, infants, or children. Do not store silver nitrate products within the reach of children.
No information about the use of silver nitrate during pregnancy is available. Adequate, well controlled studies in pregnant women have not been conducted. It is unknown whether sliver nitrate can cause harm to the fetus or affect the reproductive system. Silver nitrate should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus.
Data regarding the use of silver nitrate in breast-feeding women are not available. It is not known whether topically administered silver nitrate is excreted in human breast milk. The manufacturer does state that when ingested, silver nitrate is highly toxic to the gastrointestinal tract and central nervous system; therefore, silver nitrate should not be used on the breast when breast-feeding. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse reaction related to the maternally administered drug, health care providers are encouraged to report the adverse effect to the FDA.
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: Neisseria gonorrhoeae
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.
For the treatment of heloma:
Topical dosage:
Adults: Apply topically to affected area 2 to 3-times per week using a cotton applicator. Treatment may be continued for 2 to 3 weeks as needed.
Maximum Dosage Limits:
-Adults
3 applications/week for up to 3 weeks topically.
-Geriatric
3 applications/week for up to 3 weeks topically.
-Adolescents
Safety and efficacy have not been established.
-Children
Safety and efficacy have not been established.
-Infants
Safety and efficacy have not been established.
-Neonates
Safety and efficacy have not been established.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
Benzalkonium Chloride: (Moderate) The use of silver nitrate with benzalkonium chloride aqueous solutions may be incompatible.
Benzalkonium Chloride; Benzocaine: (Moderate) The use of silver nitrate with benzalkonium chloride aqueous solutions may be incompatible.
Collagenase: (Contraindicated) Topical collagenase can interact with other topically-applied medication products. Care should be taken to avoid topical antimicrobials, such as silver nitrate. Silver ions and agents with a low pH (< 6) inhibit the enzymatic activity of collagenase.
Keratinocytes; Fibroblasts; Collagen: (Major) Avoid the use of silver nitrate in patients receiving treatment with keratinocytes and dermal fibroblast collagen. Administering these drugs together may reduce wound repair and regeneration. In vitro data suggest silver may decrease the viability of keratinocytes and human dermal fibroblasts.
Sulfacetamide: (Major) Topical and ophthalmic sulfonamides are incompatible with preparations containing silver. Sulfacetamide sodium should not be applied to the same sites as products containing silver salts, including preparations such as silver nitrate, silver sulfadiazine, or mild silver protein.
Sulfacetamide; Sulfur: (Major) Topical and ophthalmic sulfonamides are incompatible with preparations containing silver. Sulfacetamide sodium should not be applied to the same sites as products containing silver salts, including preparations such as silver nitrate, silver sulfadiazine, or mild silver protein.
Silver nitrate promotes wound healing by exerting biocidal activity against a broad spectrum of microorganisms, including yeast, mold, and bacteria [i.e., methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE)]; however for silver nitrate to be biologically active, elemental silver must be ionized. Following topical application, the silver component is rapidly ionized to Ag+ in the presence of wound fluids or other secretions. Ionized silver (Ag+) is highly reactive and readily binds to negatively charged proteins, RNA, DNA, and chloride ions. In the presence of microorganisms, Ag+ almost immediately binds with membranes and cell wall proteins. Once silver accumulates in the bacterial cells, Ag+ poisons the microbial respiratory enzymes and electron transport system, as well as impairs some DNA functions. In yeast, Ag+ inhibits the activities of phosphomannose isomerase, an enzyme essential for the biosynthesis of fungal cell walls. These oligodynamic actions (i.e., toxic effect of metal ions on microorganisms), are dependent on the quantity of Ag+ that accumulates within the fungal or bacterial cell. Topical application of silver nitrate immediately provides high concentrations of silver to the wound; however, the silver ions released after silver nitrate application quickly becomes chemically consumed or rapidly inactivated by chloride. To overcome the rapid decline in Ag+, patients require frequent reapplication of silver nitrate. Although microbial resistance to silver itself has not been reported, a laboratory study has induced resistance using low concentrations of silver. At concentrations below the minimum inhibitory concentration (MIC), cell developed resistance through decreased permeability to silver combined an upgraded cellular efflux system to excrete intracellular silver.
Silver nitrate is administered topically
-Route-Specific Pharmacokinetics
Topical Route
In most cases, absorption of silver nitrate from the wound bed does not occur; however, silver permeating into the wound bed can be taken up by epidermal cells at the wound margin. Once absorbed, silver passes into the peripheral circulation where it can be deposited in the liver, kidneys, spleen, cornea, muscle tissue, or skin. Some excretion may occur through the urine.