Benzalkonium chloride is a surface active cationic substance whose spermatocidal effect is due to the ability to damage the membranes of spermatozoa (at the beginning of the flagella, then the heads), which makes it impossible to fertilize with damaged spermatozoa. The effect develops through 5 mni after the introduction into the vagina. Does not affect the normal microflora of the vagina (including Dodderlein's stick) and the hormonal background.
In vitro active with respect to Neisseria gonorrhoeae, Chlamydia spp., Trichomonas vaginalis, Herpes simplex a type 2, Staphylococcus aureus. He has an impact on Mycoplasma spp. and has little effect on Gardnerella vaginalis, Candida albicans, Haemophilus ducreyi and Treponema pallidum.