Yes, carprofen is a painkiller. It belongs to a class of drugs called non-steroidal anti-inflammatory drugs (NSAIDs), and it works by reducing both pain and inflammation. Carprofen is approved for use in dogs, not humans, and is most commonly sold under the brand name Rimadyl.
How Carprofen Works
Carprofen relieves pain by blocking an enzyme called COX-2, which your dog’s body uses to produce chemicals that trigger inflammation and pain signals. It’s highly selective for COX-2 over COX-1 (more than 100 to 1), which matters because COX-1 helps protect the stomach lining and support normal kidney function. This selectivity is part of why carprofen is generally well tolerated, though side effects are still possible.
Unlike corticosteroids, which also reduce inflammation but come with a long list of metabolic and immune-related side effects, NSAIDs like carprofen target the pain and swelling more directly. The result is effective pain control with fewer systemic complications for most dogs.
What Carprofen Is Prescribed For
Veterinarians most commonly prescribe carprofen for two situations: osteoarthritis and post-surgical pain. For dogs with chronic joint pain, it can be used long-term to improve mobility and comfort. For surgical recovery, it’s typically given about two hours before the procedure so pain relief is already active when the dog wakes up.
It’s available as oral tablets (including flavored chewables) and as an injectable form. The FDA lists it under multiple brand and generic names in the U.S., with Rimadyl being the most widely recognized.
Dosage Basics
The standard dose is 2 mg per pound of body weight daily. This can be given all at once or split into two doses of 1 mg per pound, morning and evening. The tablets can be given with or without food, which makes them relatively easy to administer. Your vet will determine the right schedule based on your dog’s condition, size, and overall health.
Side Effects to Watch For
Most dogs tolerate carprofen well. Stomach upset, including vomiting, diarrhea, and loss of appetite, is the most common side effect, but it occurs in fewer than 2% of dogs. These symptoms deserve attention, especially during the first three weeks of treatment, because they can occasionally signal something more serious.
The rarer but more concerning risk is an unpredictable liver reaction that occurs in roughly 1 in 5,000 dogs. This isn’t related to the dose and can’t be predicted ahead of time. It typically shows up as digestive symptoms, which is why any vomiting or appetite changes in a dog on carprofen should be reported to your vet promptly rather than dismissed as minor.
Carprofen is processed by the liver, so dogs with undiagnosed or pre-existing liver disease may not be able to handle the extra workload. The drug can also reduce blood flow to the kidneys, which is fine for healthy dogs but could push a dog with borderline kidney function into trouble. For these reasons, carprofen should not be given to dogs with known liver disease, kidney disease, or existing gastrointestinal ulcers.
Long-Term Use and Monitoring
When carprofen is prescribed for a chronic condition like arthritis, your vet will likely recommend periodic blood work to check liver and kidney function. This is especially important in older dogs, who are both the most likely to need long-term pain management and the most likely to have underlying organ issues that could complicate treatment. The first few weeks are the most critical window for catching adverse reactions early.
Why It’s Not for Humans
Carprofen was briefly available for human use in some countries but was withdrawn from the human market. It is now approved exclusively for veterinary use, primarily in dogs. The FDA labeling is explicit: “Not for human use.” The flavored chewable tablets also pose an accidental ingestion risk, both for children and for dogs who might find and eat an entire bottle. Store them in a secured location out of reach of both.
Combining Carprofen With Other Medications
Carprofen should never be combined with other NSAIDs or with corticosteroids. Stacking anti-inflammatory drugs dramatically increases the risk of stomach ulcers, kidney damage, and other serious complications. If your dog is switching from one anti-inflammatory to another, your vet will typically build in a washout period of several days between medications. Always let your vet know about any other drugs or supplements your dog is taking before starting carprofen.