The invention relates to a film-forming solution comprising: -10 to 20 % of urea, - 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.
