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Definition: opiate drug from The Columbia Encyclopedia

any of a group of drugs derived from opium. Used medicinally to relieve pain and induce sleep, they include codeine, morphine, the morphine derivative heroin, and, formerly, laudanum. Sometimes included in the group are certain synthetic drugs that have morphinelike pharmacological action. All opiates are considered controlled substances by U.S. law and are available only by prescription. Heroin is not available legally at all in the United States. See also narcotics.


Summary Article: opiates
from The Penguin Dictionary of Psychology

A broad class of drug compounds including: (a) the naturally occurring opiates, all of which are derived from the opium poppy; morphine is the drug of reference here, codeine the other commonly found alkaloid of opium; (b) the semi-synthetic opiates including heroin and various other preparations such as dihydromorphinone; (c) the synthetic opiates including methadone, meperidine and phenazocine, all of which are wholly synthetic compounds with a morphine-like pharmacological profile; (d) the narcotic antagonists, which when used in conjunction with an opiate block its effects but when used alone have opiate-like properties (note, however, that naloxone is an important exception to this pattern, being an opiate antagonist but having no analgesic or narcotic properties by itself); and (e) the ENDOGENOUS OPIATES, which occur naturally and are found in various parts of the brain.

The opiates all have both analgesic and narcotic effects; they also produce (often rapidly) both DRUG *TOLERANCE and DRUG *DEPENDENCE. As research and clinical work involving these compounds focuses less and less on those derived directly from the opium poppy, there is a move to rename the class opioids to indicate that it refers to a variety of chemicals with opium-like effects, with opiates being restricted to those compounds that derive from opium. However, this usage has not yet spread to the various compound terms, particularly those involving the endogenous chemicals, which many authorities still refer to as opiates on the grounds that they are naturally occurring and have similar biochemical structure to opium and its products.

Copyright © Arthur S. Reber, Rhiannon Allen and Emily S. Reber, 2009

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