Opiates/opioids effects terms

Opiates are compounds extracted from the milky latex contained in the unripe seed pods of the opium poppy (Papaver somniferum). Opium, morphine, and codeine are the most important opiate alkaloids found in the opium poppy. Opium was used as folk medicine for hundreds, perhaps thousands of years. In the seventeenth century opium smoking led to major addiction problems. In the first decade of the nineteenth century, morphine was isolated from opium. About 20 years later, codeine, one-fifth as strong as morphine, was isolated from both opium and morphine. In 1898, heroin, an extremely potent and addictive derivative of morphine was isolated. The invention of the hypodermic needle during the mid-nineteenth century allowed opiates to be delivered directly into the blood stream, which increases the effects of these drugs. Synthetically produced drugs with morphine-like properties are called opioids. The terms narcotic, opiate, and opioid are frequently used interchangeably. Some common synthetically produced opioids include meperidine (its trade name is Demerol) and methadone, a drug often used to treat heroin addiction. 

In the strict sense, opiates are drugs which are derived from opium and include the natural products morphine, codeine, thebaine and many semi-synthetic congeners derived from them. In the wider sense, opiates are morphine-like drugs with non-peptidic structures. The old term opiates is now more and more replaced by the term opioids which applies to any substance, whether endogenous or synthetic, pqrtidic or non-peptidic, that produces morphine-like effects through an action on opioid receptors. 

Morphine has a strong analgesic effect and has been used for the alleviation of postoperative and cancer pain since antiquity, but its use is now restricted because of its drug dependency. Morphine and its homologues were called opiates after opium, which was extracted from poppy seeds. This class of drugs are now termed opioids. 

Long-term use of oral opiates is not routinely recommended for several pharmacologic reasons. Some opioids such as morphine and codeine have the tendency to cause constipation by slowing down the peristaltic action of the bowels, which can also result in a functional ileus. This effect can be minimized by administering laxatives and/or stool softeners in patients who require longer-term opiate therapy. Prokinetic agents may also be helpful in treating opiate-related constipation. 

Correspondingly, many papers have now appeared which concern metal ion (and especially Ca +) interactions with opiates, and each year a considerable number of new reports are published. This literature has been the subject of several reviews (JL- ). In the present article this body of work is considered in terms of the general hypothesis that neuronal Ca + levels control the nociceptive state and that opioids, both endogenous and exogenous, exert their main effects via changes in Ca + disposition. 

The term mental dependence is based on the euphoric effect of opioids. The loss of euphoria, concurrent with the appearance of physical withdrawal symptoms, makes it even more difficult for patients to overcome their addiction. For the therapeutic treatment of addiction, as well as for acute opiate poisoning, opiate antagonists (e.g. Naloxone) have been developed. 

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