arprofen, marketed under many brand names worldwide, is a nonsteroidal anti-inflammatory drug (NSAID) that veterinarians prescribe as a supportive treatment for various conditions in animals. It provides day-to-day treatment for pain and inflammation from various kinds of joint pain as well as post-operative pain. Carprofen reduces inflammation by inhibition of COX-1 and COX-2; its specificity for COX-2 varies from species to species.
Most dogs respond well to carprofen use, but like all NSAIDs, it may cause gastrointestinal, liver and kidney problems in some patients.
After introduction, significant anecdotal reports of sudden animal deaths from its use arose. To date[when?], the FDA has received more than 6,000 adverse reaction reports about the drug (manufactured by Pfizer). As a result, the FDA requested that Pfizer advise consumers in their advertising that death is a possible side effect. Pfizer refused and pulled their advertising; however, they now include death as a possible side effect on the drug label. Plans call for a "Dear Doctor" letter to advise veterinarians, and a safety sheet attached to pill packages.
Adverse effects include:
Loss of appetite
Increase in thirst
Increase in urination
Fatigue and/or lethargy (drowsiness)
Loss of coordination
Liver dysfunction: jaundice (yellowing of eyes)
Blood or dark tar-like material in urine or stools
Staggering, stumbling, weakness or partial paralysis, full paralysis
Change in skin (redness, scabs, or scratching)
Change in behavior (such as decreased or increased activity level, seizure or aggression)
Effects of overdose include gastritis and ulcer formation.