RESUMEN
Butorphanol tartrate (4 mg and 8 mg) was compared to codeine phosphate (60 mg) and placebo for oral analgesic activity and side-effects employing a double-blind design in ninety-three out-patients suffering from moderate to very severe musculoskeletal pain. The study duration was 72 hours with medication administered every 4 to 6 hours (four times daily) for a total of twelve doses per patient. The results demonstrate that both the 4 mg and 8 mg doses of butorphanol were significantly better (p less than 0.u5) than placebo. While codeine 60 mg also proved active, it appears to be less efficacious than the high dose of butorphanol. The peak effect appeared to be evident in 1 to 2 hours. Butorphanol may be at least seven times more potent than codeine on a milligram basis. Although no serious side-effects were observed, butorphanol appeared to present a greater incidence of side-effects than codeine and placebo in this study.