cetrimide bacteriostatic antiseptic and surfactant quaternary ammonium compound; active against a narrow spectrum of Gram-positive bacteria; non-effective against Pseudomonas , fungi and spore forms; may be combined with chlorhexidine (0.015% chlorhexidine and 0.15% cetrimide, e.g. Tisept); cytotoxic; not routinely used to cleanse ulcers