Benzalkonium chloride

• Approved Indications:
• Topical antiseptic and disinfectant for skin and mucous membranes.
• Prevention and treatment of superficial infections in minor cuts, wounds, abrasions, and burns.
• Disinfection of instruments and surfaces in healthcare and laboratory settings.
• Preservative agent in ophthalmic, nasal, and otic solutions.
• Used in hand sanitizers, antiseptic wipes, and cleansing agents.
• Off-label Uses:
• Adjunct antiseptic in oral rinses and gargles.
• Used in some nasal sprays for relief of nasal congestion due to its antimicrobial properties.
• Occasionally used in veterinary antiseptics.

• Route: Topical application (solutions, creams, ointments), ophthalmic drops, nasal sprays, or surface disinfectants.
• Topical Skin Use: Apply antiseptic solution or ointment to affected area 1–3 times daily or as directed until healing occurs.
• Ophthalmic Use: Typically 0.01%–0.02% concentration in eye drops as a preservative; follow specific product dosing instructions.
• Nasal Use: Usually 0.01%–0.05% concentration; administered as per product labeling.
• Instrument Disinfection: Use according to manufacturer instructions for dilution and contact time.
• Special Populations: Use cautiously in infants and children, avoid excessive or prolonged use. Avoid application to large areas of broken skin to minimize systemic absorption risk.

Benzalkonium chloride is a cationic surfactant and quaternary ammonium compound that disrupts microbial cell membranes by interacting with phospholipids and proteins. This leads to increased membrane permeability, leakage of intracellular contents, and ultimately microbial cell death. It exhibits broad-spectrum antimicrobial activity against bacteria (both gram-positive and gram-negative), fungi, and some viruses, making it an effective antiseptic and disinfectant agent.

• Absorption: Minimal systemic absorption when applied topically on intact skin or mucous membranes.
• Distribution: Confined mainly to the application site; negligible systemic distribution.
• Metabolism: Not metabolized significantly due to limited absorption.
• Excretion: Trace amounts, if any, are eliminated via renal excretion.
• Onset & Duration: Rapid onset of antimicrobial action on contact; duration depends on formulation and application frequency.

• Pregnancy: No well-controlled studies in pregnant women; topical use considered low risk but should be used only if clearly needed.
• Lactation: Minimal systemic absorption; unlikely to affect breastfeeding infants. Use with caution and avoid application on large areas.

• Primary Therapeutic Class: Antiseptic and Disinfectant
• Subclass: Quaternary Ammonium Compound

• Known hypersensitivity to benzalkonium chloride or any excipients in the formulation.
• Avoid use on large, open, or deep wounds due to potential irritation.
• Contraindicated in cases of severe mucosal irritation or inflammation where application may exacerbate damage.

• May cause local irritation, burning, or allergic contact dermatitis with prolonged or excessive use.
• Avoid contact with eyes, except in formulations intended for ophthalmic use.
• Use cautiously in infants and patients with sensitive skin or mucosa.
• Some microorganisms have shown reduced susceptibility; prolonged use may lead to resistance.
• Not suitable for injection or internal use.
• Discontinue if signs of hypersensitivity or severe irritation occur.

• Common:
• Mild local irritation, redness, or stinging sensation at application site.
• Rare:
• Allergic contact dermatitis, urticaria.
• Eye irritation if used improperly in ophthalmic products.
• Potential bronchospasm or respiratory irritation if inhaled in high concentrations.

• No significant systemic drug interactions due to minimal absorption.
• May interact with other topical agents causing additive irritation.
• Incompatible with anionic detergents and some organic materials which reduce its antimicrobial activity.

• Continued recommendation as an effective topical antiseptic in wound care and infection prevention.
• Regulatory bodies highlight careful formulation concentration limits to balance efficacy and minimize irritation risk.
• Increased scrutiny on microbial resistance patterns to quaternary ammonium compounds in healthcare settings.

• Store at 20°C to 25°C (68°F to 77°F).
• Protect from freezing, excessive heat, and direct sunlight.
• Keep container tightly closed to prevent contamination.
• Avoid prolonged storage after opening as efficacy may decline.