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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 Encyclopedia of Addictions

According to the strict definition, opiates are drugs derived from opium, and opioids are opiate-like substances either made in the body—the endogenous opioids known as endorphins, enkephalins, or dynorphins—or manufactured in a laboratory, such as methadone. The terms are often used interchangeably, however, and the drugs are also referred to as narcotics—although this word is falling into disuse because the meaning, “related to stupor or a stuporous state,” is somewhat imprecise.

Opium, the parent drug from which other opiates are derived, comes from the seedpods of the Papaver somniferum poppy. Although the plant can be grown throughout much of the world, only low morphine-producing varieties may be grown in the West. The stronger morphine-producing varieties are grown in Mediterranean regions of the world, and the importation of the opium derivatives they produce is tightly controlled.

The opiates produced naturally from the plant include opium itself, morphine, codeine, and thebaine. Thebaine tends to produce stimulatory rather than depressant effects and is, in itself, not a drug of abuse. However, it is a highly addictive substance converted into synthetic opiates such as oxycodone and oxymorphone or used in the manufacture of opiate-addiction treatment drugs such as buprenorphine. Other derivatives synthesized from the natural substances found in opium are heroin, hydromorphone, and hydrocodone. Drugs that mimic the activity of opium and the opium derivatives but have been created in laboratories are meperidine, dextropropoxyphene, fentanyl, pentazocine, and butorphanol. Methadone, a synthetic agonist developed during World War II as a substitute pain medicine to address a morphine shortage, has since become useful in the treatment of addiction to opiates. Two other drugs have also been developed for treatment purposes: levo-alpha-acetyl-methadol (LAAM) and buprenorphine. Based on its medical use and its inherent addictive properties, each opiate, or each substance like a cough medicine that contains an opiate, is placed into one of the Controlled Substances Act's 5 schedules.

Opiates Chart

Opiates should not be used with substances like alcohol or other depressants that also suppress the central nervous system, unless they are prescribed by a physician, because the interaction of these drugs can be deadly. When used under medical supervision to relieve pain, opiates are usually not addicting unless the patient is already addicted to drugs. Nevertheless, when the drugs are withdrawn, some pain patients experience discomfort known as hospital flu as their systems adjust to the drugs' absence. This differs from addiction in that it does not involve compulsive, out-of-control behavior that persists despite negative consequences; it is instead the body's adjustment to the drug's absence.

Opiates are defined by their morphine-like effects to relieve severe pain. They are also prescribed as antidiarrheals and cough suppressants. They can be injected, smoked, sniffed, delivered via lozenge-like troches that the user lets dissolve in his or her mouth, or inserted rectally in suppositories. As with any drug, the effect depends on the method of administration and the dosage, but opiates' affinity for the brain's opioid receptors can result in psychological craving that often persists for a significant period of time after physical dependence has been broken. Under nonmedical conditions, opiates tend to produce drowsiness, a release from tension and anxiety, and a sense of euphoric well-being. They can also produce an inability to concentrate, nausea, constipation, and, most threatening, suppression of breathing. Since tolerance builds quickly, cases of opiate overdosing—which can be lethal—are seen often in emergency rooms in cities or states where drug abuse is widespread. The symptoms of an overdose are pinpoint pupils, confusion, convulsions, and cold clammy skin. Respiratory depression is often the cause of death. The other significant dangers of opiate use include infections from dirty needles or organ damage from the adulterants added to many street drugs. Examples of the conditions drug use can produce include AIDS, hepatitis, inflammation around the heart or brain, and lung or brain abscesses. These can threaten users' lives long after drug use has ceased.

Withdrawal from opiates can be very unpleasant, taking anywhere from 7 to 10 days to run its course, but is seldom life threatening. Early symptoms include yawning, watery eyes, sweating, and restlessness, followed by severe depression, insomnia, cramps, restlessness, diarrhea and vomiting, chills, and goose bumps, the symptom that gave rise to the term “cold turkey.”

Powerful pain relievers have an essential role in medicine, but healthcare providers are careful about inadvertently fostering addiction in their patients despite the likelihood that opiates, if used solely to relieve pain, are relatively safe. This continues to be controversial, however, and most physicians prescribe opiates with caution. In the meantime, researchers continue to try to find or synthesize substances that can offer the pain-relieving efficacy of opiates without the addictive properties.

See also Drug Classes; Appendix B.

Further Reading

U.S. Department of Health and Human Services, National Institute on Drug Abuse (NIDA), June 2007. Retrieved from

U.S. Department of Health and Human Services, Substance Abuse and Mental Health Services Administration (SAMHSA), August 2007. Retrieved from

U.S. Department of Justice, Drug Enforcement Administration (DEA), March 2008. Retrieved from

  • Califano, Joseph Joseph. Jr. High Society: How Substance Abuse Ravages America and What to Do About It. New York: Perseus Books, 2007.
  • Hoffman, John, and Froemke, Susan, eds. Addiction: Why Can't They Just Stop? New York: Rodale, 2007.
  • Home Box Office (HBO). In partnership with the Robert Wood Johnson Foundation, the National Institute on Drug Abuse, and the National Institute on Alcohol Abuse and Alcoholism. Addiction: Why Can't They Just Stop? Documentary. March 2007.
  • Ketcham, Katherine, Pace, Nicholas A. Teens Under the Influence: The Truth About Kids, Alcohol, and Other Drugs. New York: Ballantine Books, 2003.
  • Copyright © 2009 by Greenwood Publishing Group

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