I got excited when I read the headline and leader to an article on CatChannel.com.

New Cat Painkiller
The FDA has approved a new drug to control postoperative pain in cats

Feline pain management options are woefully few. A new pain killer for cats would be a very welcome thing indeed. Sadly, based upon a few brief words in the body of the article, I already have serious concerns about the product’s safety.

The U.S. Food and Drug Administration has approved Novartis Animal Health Inc.s Onsior (robenacoxib) Tablets in cats for the control of postoperative pain and inflammation associated with orthopedic surgery, ovariohysterectomy and castration.

Any drug name that ends with coxib is in a class of non-steriodal anti-inflammatory drugs (NSAIDs) called COX-2 inhibitors. The most famous COX-2 inhibitors were Vioxx (rofecoxib) and Celebrex (celecoxib). These two human drugs were at the center of a trade war, side-effect cover-up (in the case of Vioxx), and scandal not long after FDA approved them. At the end of the melee, Vioxx was withdrawn from the market. Celebrex is still available, but it has not turned out to be the miracle drug (or earner) that its maker hoped for.

NSAIDs and cats don’t mix well. I remember when Metacam (meloxicam), another NSAID, was unleashed upon the cats of America with great fanfare. Much less fanfare occurred as the product fell out of favor and had its labeling changed due to an unacceptable risk of fatal complications from the product when used as directed in cats.

I don’t know whether Onsior will stand the tests of time and safety in cats, but my hunch is that it will not. I won’t be rushing to administer it to my feline patients for now.