If your cat or your dog has a skin infection or skin allergies, your veterinarian may prescribe a medicated shampoo. Most of the time, mild skin infections or allergies can be treated just with shampoo, eliminating the use of oral antibiotics. Chlorex is an antifungal, antimicrobial, cleansing and deodorizing shampoo for cats, dogs, and horses. Chlorex contains Chlorhexidine (a powerful antiseptic) and penetrating and softening agents, making it a super-effective shampoo.