About Cetrimide Quaternary ammonium compound, a cationic surfactant, Antiseptic agent, a detergent ,disinfectant. Mechanism of Action of Cetrimide Cetrimide is a cationic surfactant. It destroys or damages the cell membrane by lowering surface tension. It causes microbial protein denaturation and produces antiseptic action. About Chlorhexidine A bisbiguanide antimicrobial agent, Anti-infective, antiseptic. Mechanism of Action of Chlorhexidine This drug has positive charge so it attach to the negative charge cell wall. This destabilizes and destroys the integrity and penetrates bacterial cell membranes. It results precipitation of the cytoplasm and interferes with membrane function by inhibiting oxygen utilization leading to a decrease in cellular ATP levels and cell death. In gram-negative bacteria, chlorhexidine affects the outer membrane allowing the release of periplasmic enzymes.