The article presents the data of domestic and foreign randomized clinical trials on the efficacy of naftifine hydrochloride (Exoderil) in topical treatment of onychomycoses and dermatophytoses of the smooth skin. The criteria for selection of a topical antimycotic agent for onychomycosis that are based on the intensity of anti-keratolytic and antimicrobial action are described on the example of naftifine hydrochloride. A wide range of the antifungal activity of naftifine is confirmed by the in vitro proven absence of resistance of pathogens to the drug.