Clara Mason, DVM

44 Cloverleaf Street
Winfield, WV 25213

(304)340-1401

claramasondvm.com

Ethical and Legal ramifications of using and prescribing Previcox extralabel in horses.

In 2016, Merial launched Equioxx in TABLET form for your horse. The tablets are scored and can be split in half for smaller horses.  Prices are similar in cost between Previcox for dogs and Equioxx for horses.

Previcox,  (drug name: Firocoxib) is manufactured by Merial and is an economical, effective and enteric-friendly NSAID that is used in dogs to control pain and inflammation due to osteoarthritis. Equioxx, (drug name: Firocoxib) is an effective and enteric-friendly NSAID used in horses to control pain and inflammation.  However, it is not as economical as the dog version.  The increased cost may attributed to the cost of placing the firocoxib into paste form for individual administration. 

Often, horse clients ask vets to dispense the dog version of firocoxib rather than the horse version in order to save money.  This is understandable especially in today's troubled economy. At a dose of 0.1 mg/kg, Previcox seems to be efficacious in horses.  But despite its efficacy, the FDA standards dictate that Previcox is illegal to prescribe or dispense for horses because an approved drug for horses, Equioxx, already exists. In December 2012, the AAEP, Merial, FDA and the AVMA met in Anaheim to try to sort through the quandary of using firocoxib extralable in horses (drug in different forms for another species than what is on the label).

According to the law as it is written, it is clear that the use of Previcox in the horse is seen as illegal by the FDA and AVMA. However, the manufacturer - Merial, expressed interest in helping veterinarians understand the ramifications of such. use.  The committee developed the following conclusions:

1.  The horse owner has no recourse from Merial if the horse experiences an adverse reaction of any type for any reason. Unfortunately, if there is a legal recourse, the owner of the horse more than likely will pursue legal action against the vet since it is denied legal cause against the manufacturer. 

2. Though having the client sign a legal waiver when their horse is receiving Previcox will not give the vet much protection against  litigation from the client, a signed paper will open discussion between the vet and client about not using Previcox over Equioxx.

3. The FDA may initiate enforcement action against the vet for prescribing Previcox.  This may potentially a federal indictment if the FDA chooses to pursue the issue.

4.  The correct oral dosage of firocoxib in horses is 0.1mg/kg.

The bottom line is that your horse should be on the correct dosage of firocoxib and for the limited amount of time prescribed by the manufacturer.