April Knudson, DVM, is an equine specialist with Merial Veterinary Services. She has a special interest in equine gastrointestinal health, infectious disease, and lameness. She holds a doctor of veterinary medicine from the University of California-Davis. Here, she answers a question about how to evaluate the products available to horse owners.

Question: There are so many different versions of drugs available to purchase for my horse. How do I know which ones really work and are safe to use?

Answer: As with any other area of equine health care, it is always best to consult your veterinarian about providing the best possible medicine, including the risks and benefits of any product before giving it to your horse. There are many companies out there making claims that their products are "just like" others you may have used, but this is often just not the case.

When you decide to buy a product–specifically a drug or a supplement–for your horse, it’s important to make sure you really know what you are getting. Having a better understanding of a few definitions may help as you and your veterinarian evaluate and make decisions about your horse’s health care