Carprofen is a non-steroidal anti-inflammatory drug (NSAID) commonly used in animals to combat pain and inflammation, particularly as associated with osteoarthritis. Like many NSAIDs, carprofen inhibits both cyclooxygenases COX-1 and COX-2 (IC50s = 22.3 and 3.9 μM, respectively). It also inhibits fatty acid amide hydrolase (IC50 = 74 μM), blocking the metabolism of the cannabinoid receptor ligand, arachidonoyl ethanolamide .