Carprofen (Rimadyl), Canine

Carprofen (Dogs Only)

By Dr. Karen Burgess

Brand name and formulations

  • Rimadyl and generic
  • Tablets, Chewable Tablets, and Injectable

What is carprofen used for?

Carprofen is labeled for the treatment of inflammation and pain that is often used in the management of osteoarthritis in dogs only. It is also commonly prescribed after surgery and to treat soft tissue injuries such as sprains/strains.

What is carprofen?

Carprofen is a non-steroidal anti-inflammatory (NSAID). While carprofen is not used in humans, common human NSAIDs include include aspirin, Advil (ibuprofen), Aleve (naproxen), Celebrex (celecoxib) and Vioxx (rofecoxib). Dogs and humans do not metabolize NSAIDs in the same way and for this reason human NSAIDS should never be given to dogs.

How is carprofen given and what if a dose is missed?

Carprofen is typically prescribed for once daily dosing. If a dose is missed and it is less than 12 hours late, go ahead and give missed dose. If it is within 12 hours of the next dose, skip a dose and resume regular schedule with next dose. Care should be taken to not allow dogs access to the pill container of chewable Rimadyl as it is very palatable and overdose can occur with excessive ingestion.

What is carprofen’s background and what side effects are associated with carprofen?

NSAIDs as a class have been associated with stomach ulceration and potential rupture, platelet dysfunction leading to potential clotting issues, and kidney failure related to decreased blood flow to the kidneys. Rimadyl (carprofen) was developed in 1997 as an NSAID option for dogs that would minimize these potential side effects.

Approximately 1 out of 1000 chance that a dog put on carprofen will develop gastrointestinal signs such as vomiting, diarrhea, and loss of appetite. If these signs develop, the medication should be stopped and follow up laboratory work performed to evaluate for more significant problems. Approximately 1 in 5000 will develop an idiosyncratic (meaning not dose dependent or predictable) reaction affecting the liver. This potentially fatal reaction often presents initially looking very similar to those that just have mild stomach upset. Blood tests help differentiate between the two conditions.

Dogs with decreased liver or kidney function may show worsening of their condition on Rimadyl. For this reason bloodwork is typically recommended prior to and after two weeks of therapy with carprofen.

What drugs should not be given with carprofen?

NSAIDs as a class should never be given at the same time as another NSAID or steroid. This can be life threatening. There should be a seven day “washout” period when changing from one NSAID to another. If aspirin has been given, another NSAID should not be given for fourteen days. Phenobarbital and enalapril may also be problematic if used in conjunction with carprofen.

What follow up is necessary with carprofen use?

Laboratory work should ideally be done prior to carprofen use and then again 2 weeks later. Maintenance testing should then occur at a minimum of once a year.