Equioxx vs. Previcox in Horses

July 5, 2011 (published) | December 22, 2014 (revised)

Equioxx is a pain reliever approved for horses, but it is fairly expensive. The drug is made by Merial, who also makes the same drug approved for dogs called Previcox. On a mg per mg basis, Previcox for dogs is much less expensive than Equioxx for horseseven thoughit is the same drug. Consequently, many horse owners want to use the dog drug Previcox for their horse because it is less expensive, and some vets have prescribed it when horse owners ask them to dispense it.

Your veterinarian also wants to treat your horse with the most effective medication available and does not want you to spend more money than necessary. However, realize it is illegal for your vet to prescribe Previcox, a drug approved only for use in dogs, for your horse because the same drug is already approved for horses. There are several concerns about asking your vet to prescribe Previcox and the first is that if your horse experiences a reaction, the company will not stand behind the vet. Also, since the drug would have been prescribed illegally, the vet’s insurance will not cover the vet because an illegal prescription was written. Also, if they choose, the FDA can issue a federal indictment for the veterinarian. When people ask their veterinarians to prescribe a dog drug for a horse, they are asking those veterinarians to break the law and put their license – their livelihood - in jeopardy. So when you ask your vet to prescribe a drug that is illegal, it is not because the vet does not want to save you money, but as you can see there are serious potential consequences for the vet by doing so. Consider this when asking your vet for unapproved drugs for any of your animals.

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