Drugs derived from opium, the dried juice of the oriental poppy seed. The pharmacologically active substances, which constitute approximately 25% of the extract, are the alkaloids morphine, codeine, and papaverine. The newer synthetic compounds which resemble morphine in their action are called opioids.
The principal effect of opium and opioids is to relieve pain. Even today morphine remains the best analgesic. It also assuages anxiety and causes slight drowsiness, relaxation, and a euphoric state of mind. These psychic effects are so agreeable that many troubled individuals seek solace by ingesting, smoking, or injecting opiates.
Codeine has an action similar to morphine, but its analgesic effects are less. Papaverine has almost no analgesic action, and is used as an antispasmodic to relieve vascular spasm and undesirable contraction of smooth muscle. See also Analgesic; Narcotic.
