Carprofen was used in humans for almost 10 years, starting in 1988. It was used for the same conditions as in dogs, viz., joint pain and inflammation. Side effects tended to be mild, usually consisting of nausea or gastro-intestinal pain and diarrhea. Carprofen was available only by prescription in 150 to 600 mg doses. Dosage over 250 mg was only for relieving pain after severe trauma, such as post-surgery inflammation.  150 mg doses were commonly used to relieve the pain of arthritis, while 200 mg doses were commonly prescribed in cases of severe arthritis or severe inflammation pain.  The drug was taken orally. Pfizer voluntarily removed it from the market for human use on commercial grounds. 
Recovery time increased with increasing dose. Increasing doses of ALFAXAN resulted in decreases in heart rate, respiratory rate, and blood pressure within 15 minutes postinduction. The lowest RR (18 breaths per minute) seen at 15 and 25 mg/kg occurred at 50 and 5 minutes post-dose respectively. Cats in the 5 mg/kg dose group reached a minimum of 23 breaths per minute at 10 minutes post-dose. During the initial 5 minutes after induction, there was 1 episode of apnea at 5 mg/kg, 6 episodes of apnea at 15 mg/kg, and 3 episodes of apnea at 25 mg/kg. Decreases in mean hemoglobin saturation (SpO 2 ) were not dose related. The lowest mean hemoglobin concentration for cats in both the 5 and 15 mg/kg dose groups were approximately 88%. For cats that received 25 mg/kg, the lowest SpO 2 was 83%. Mean systolic and diastolic blood pressure decreased with increasing dose. No abnormal cardiac arrhythmias were noted during the study (ECG observed but not recorded). Clinical pathology abnormalities were not clinically significant for all groups. Abnormal necropsy and histopathology findings were associated with injection site trauma consistent with intravenous injection and repeat catheterization. No pain on injection was reported.