Abstract: A method for treating pathological conditions of the nail, particularly onychomycosis, is described. The method comprises the breaching the protective keratin of the nail to form an opening therein, placing a caustic-keratolytic agent in the opening to enlarge it, and treating the nail through the opening with topical therapeutic agents for the pathological condition being treated, for instance, an antifungal agent for onychomycosis. In addition, thick callouses and painful plantar warts can be removed with modifications of this method.