Benzalkonium Chloride, also known as Zephiran, is a non-oxidizing disinfectant and a widely used cationic surfactant with broad-spectrum antibacterial properties. In aqueous solution, it dissociates into positively charged active groups, providing both cleaning and bactericidal effects. It acts rapidly and effectively against bacteria—especially Gram-positive species—while exhibiting low toxicity and minimal irritation to skin and mucous membranes.

Its antibacterial mechanism involves altering the permeability of the bacterial cytoplasmic membrane. This leads to leakage of intracellular components, disruption of metabolic processes, and ultimately microbial death.