Many horse owners groom their animals daily, especially when riding regularly or showing, and they use a wide variety of topical products–shampoos and hair conditioners, mane and tail detanglers, stain removers, coat polishes, fly repellents, etc. Jean Greek, DVM, Dipl. ACVD, a veterinary dermatologist at CARE (California Animal Referral & Emergency) Hospital in Santa Barbara, Calif., says horse owners often use anything and everything on their horses, sometimes without thinking about possible reactions or skin sensitivities. "Fortunately, there are not a lot of contact allergies in horses, compared to humans, but on occasion a certain product may be irritating to your particular horse," she says.

The biggest problem she sees in her practice is skin disease passed around by use of shared grooming tools. "A horse ends up with ringworm (a common skin infection caused by ringworm fungi–dermatophytes) or some other transmissible skin problem because owners have been sharing brushes, clippers, etc.," she says. "Ringworm, especially, can be readily spread. You may use a friend’s equipment at a show and bring home ringworm to your farm or stable. Even a normal-looking horse can carry fungi on the skin; you may think you are borrowing tools from someone whose horse is perfectly healthy, and your horse develops ringworm."

Owners often try new products or something recommended by their friend, but he or she should test a small amount on the horse’s neck to check for sensitivity before putting it all over your horse. Then if there’s a reaction, it won’t be made worse by a blanket or saddle pad rubbing it. "If your horse is sensitive, it won’t affect his whole body," Greek notes. "If he does react, this doesn’t mean it’s a bad product; it just means your horse is sensitive. You might need to try several products before you find one that works best for your horse