Onychomycosis is the most common form of fungal infection in humans. It affects men much more often than women. It is not only an aesthetic problem, and if left untreated, it can lead to many complications. The treatment is most often used nail polishes containing substances with antifungal activity, such as cyclopirox and amorolfin. In addition, during treatment, it is worth using disinfectants for feet and footwear.