Pain relief in the post-operative period: a comparative trial of morphine and a new analgesic buprenorphine.

In a comparative trial, buprenorphine 0-3 mg or morphine 10 mg was administered intramuscularly to patients post-operatively. The new drug buprenorphine produced more pain relief than morphine and appeared to have a longer duration of action. The side-effects produced by the two drugs were similar, as were the effect on respiratory and cardiovascular measurements.