The invention relates to a film-forming solution comprising: &minus；10 to 20% of urea, &minus；5 to 15% of film-forming polymer, 45 to 65% of a polar solvent, 1 to 20% of a co-solvent, 0.01 to 5% of a plasticizer selected from the list consisting of diethyl phthalate, triethyl citrate, dibutyl sebacate, diethyl sebacate, dibutyl phthalate, acetyltriethyl citrate, and polyethylene glycols, and water up to 100% intended for treating ungual fungic infections and nail psoriasis.
