The analgesic efficacy of two doses of conorphone (20 and 40 mg), a mixed agonist-antagonist analgesic, were compared to two doses of codeine for postoperative pain in the oral surgery model. Each subject received 2 of the 4 possible treatment at two separate sessions in an incomplete block, single crossover design. Both doses of conorphone and the 60 mg dose of codeine were superior to 30 mg of codeine for the various indices of analgesic activity. The 40 mg dose of conorphone resulted in a high incidence of side effects (25/30 subjects) such as drowsiness, dizziness, nausea and vomiting. The low dose of conorphone resulted in side effects similar to 60 mg of codeine with the exception of a greater incidence of drowsiness. These data suggest that while 40 mg of conorphone may not be well tolerated clinically, 20 mg of conorphone may be an alternative to 60 mg of codeine for postoperative pain.