Octenidine is a cationic surfactant that is active against both gram-positive and Gram-negative bacteria. In vitro studies Octenidineconcentrationsoflessthan1.5 microns (0.94 mu g/mL) causesagreaterthan99% reductionoftestedmicrobialpopulationwithin15m in.Staphylococcusepidermidisisthemostsusceptibleofthetestorganisms,andE.coliandC.albicansaretheleastsusceptible. In vivo study Theantimicrobialactivityofoctenidinehydrochloride Chemicalbookismaintainedwhenappliedtotheskinofthehandsandfeeto (OCT) Fcynomolgusmonkeys Aqueousoctenidine, ataconcentrationof0.2 to1.6% reducesresidentmicroflorapopulationsfrom90to99. The 98% Asign ificantreductioninplaquescoreisobservedonthebuccaltoothsurfacesafterdailytopicalapplicationof1%solutionsofoctenidineandc hlorhexidinefor7d; octenidineismoreeffectivethanchlorhexidine.