Fung-A-Way can be used on horses, dogs, and cats. Fung-A-Way is a fast-acting topical solution for treating Summer Itch, Girth Itch, Ringworm and other fungal problems. Topical application should result in an apparent improvement in days. Fung-A-Way contains 0.15% Benzalconium Chloride, Carbamide and Allontoin.