Analgesic evaluation of butorphanol in patients with postoperative wound pain.

Two agonist/antagonist analgesics, butorphanol tartrate (test) and pentazocine hydrochloride (standard), were compared in volunteer informed patients experiencing postoperative wound pain. The relative potency (p) is 0.04 (1 mg butorphanol equals 24.3 mg of pentazocine lactate) with upper and lower confidence limits of 0.01 and 0.07 respectively. Butorphanol tartrate in the higher dose appears to have longer duration of effect. The side effects were comparable in the population studied.