Butorphanol/acetaminophen double-blind study in postoperative pain.

An oral butorphanol/acetaminophen (4 mg/650 mg) combination product was evaluated for analgesic activity in 120 postoperative patients employing a double-blind experimental design. The combination product was significantly (p less than 0.05) superior to either butorphanol (4 mg) or acetaminophen (650 mg) as well as placebo. Except for acetaminophen which was only significantly different (p less than 0.05) from placebo at 2 hours according to pain relief, all other treatments were superior to placebo over the entire 4 hour observation period. The data demonstrate that butorphanol and acetaminophen have at least additive analgesic activity with a suggestion of synergism. A single tablet dose of the combination product (butorphanol 2 mg/acetaminophen 325 mg) was evaluated in a second study involving 60 patients and was significantly (p less than 0.05) superior to placebo. Both studies demonstrate that the butorphanol/acetaminophen combination product has potent analgesic activity with a minimal side effect profile.