Cocaine and morphine interaction in acute and chronic cancer pain.

An evaluation of the analgesic, mood and side effects of the combination of intramuscular morphine and oral cocaine was conducted in 17 patients with postoperative pain and 19 others with chronic malignant pain for the purpose of assessing the therapeutic merits of so-called 'euphoriant' elixirs in the management of pain in cancer patients. The study was designed as a randomized and double-blind single dose but complete cross-over comparison of the combination of 10 mg intramuscular morphine and 10 mg oral cocaine with morphine alone, cocaine alone, and placebo. While patients clearly discriminated between the analgesic effects of morphine and placebo, there were no differences in the analgesic responses to cocaine and placebo, or in responses to morphine and the combination of morphine and cocaine in either patient group.