Synthetic opiates

The identification of the morphine receptor spurred an effort in many laboratories to find an endogenous agonist for which that receptor was normally intended. Ultimately, a pair of pentapeptides that bound quite tightly to opiate receptors were isolated from mammalian brains. These peptides, called enkephalins (2, 3), show many of the activities of synthetic opiates in isolated organ systems. They do in fact show analgesic activity when injected directly into the brain. It is thought that lack of activity by other routes of administration is due to their rapid inactivation by peptide cleaving enzymes. 

How similar are natural and synthetic opiates in terms of structure and effects ... 

Methadone A synthetic opiate used in the maintenance therapy of former heroin and morphine dependents. 

Conventional drug therapy for opiate withdrawal has been methadone, a synthetic opiate. Usual starting doses have been 20 to 40 mg/day. The dosage can be tapered in decrements of 5 to 10 mg/day until discontinued. Some clinicians use discontinuation schedules over 30 days or over 180 days. 

A comparable reaction was seen decades ago in the metabolism of methadone [173 - 175]. This well-known synthetic opiate undergoes A-demeth-ylation as a major metabolic reaction in humans and laboratory animals. The resulting secondary amine (11.168, Fig. 11.21) has never been isolated, as it undergoes practically instantaneous cyclization. The reaction is believed to proceed via the carbinolamine with formation of metabolite 11.169 as the major urinary metabolite in humans. This structurally intriguing basic compound is, in its neutral form, a pyrrolidine with an exocyclic C=C bond,... 

There are many legal medicines that use opiates or opiate-like substances. Most of the opiate-based medicines used today are not made from natural opiates, but are either synthetic or semi-synthetic. Synthetic opiate drugs are not actually opiates at all they are merely different chemicals that act like opiates. Semi-synthetics are those drugs that involve changing the chemical structure of a natural opiate. An example of this is heroin, which is a human-made variation of morphine. Morphine and codeine are the principal natural opiates used as medicines and what follows are descriptions of the other most frequently used opiate-based medicines. 

More than half (57 %) of all seizure cases involved cannabis (herb, resin, oil, plants and seeds). Opiates (opium, morphine, heroin, synthetic opiates and poppy seeds), accounted for 17 per cent, with heroin alone accounting for 14 per cent of the total. This is followed by seizures of the amphetamine-type stimulants (12 %). About half of these seizures (or 5.5 % of the total) is accounted for by methamphetamine, followed by amphetamine (2.5 %) and ecstasy (2%) the rest (2 %) includes Captagon tablets (Near East) and Maxiton Forte (Egypt), ephedrone (methcathinone) and various undefined amphetamines. Coca products account for 9 percent of global seizure cases the bulk of coca related seizure cases concern cocaine (8 % of total). 

About 71 per cent of the worlds 15.6 million opiates users abuse heroin. This amounts to 11 million people. The proportions, however, vary significantly by region. Whereas almost all opiates consumers in Africa reportedly use heroin, only one third consume that substance in Oceania. This particular pattern is due to difficulties in accessing heroin and the availability of synthetic opiates. 

LAAM (LEVO-ALPHA-ACETYLMETHADOL) Like methadone, LAAM is a synthetic opiate used to treat heroin addiction, blunting withdrawal for up to 72 hours. 

Because any opiate derivative will suffice to soothe heroin cravings associated with withdrawal, methadone, a synthetic opiate that has no sedating side effects, has been an effective treatment for heroin and morphine addiction for more than 30 years. The medication is taken orally and suppresses narcotic withdrawal for a period of 24 to 36 hours. Methadone can be taken continuously for 10 years or longer with no harmful side effects. 

Like methadone, LAAM (levo-alpha-acetyl-methadol) is a synthetic opiate used to treat heroin addiction. LAAM can block the effects of heroin for up to 72 hours. This makes outpatient treatment much more convenient, given that patients need to dose only two to three times a week. Naloxone and naltrexone are new medications that are also effective at blocking the pleasurable effects of heroin, helping motivated individuals to abstain. 

This synthetic opiate was introduced in 1965 to manage opioid dependence and has been successfully used as an aid to abstinence since that time. Methadone is a racemate, the R-enantiomer being the pharmacologically active form of the drug. This isomer shows a 10-fold higher affinity for the... 

Perhaps it may be possible to use this diversity and selectivity of action to develop new synthetic opiates that will have therapeutic advantages over morphine and its analogues which, in one form or another, have been used by mankind for nearly 2000 years. 

Opioids (heroin) are frequently used in combination with cocaine (speedball) by persons generally involved in crime. Early death may occur as a result of their use. Heroin addicts acquire bacterial infections producing skin abscesses, pulmonary infections, endocarditis, viral hepatitis, and acquired immunodeficiency syndrome (AIDS). There is a range of treatment options for heroin addiction, including medication and behavioral therapies. Methadone, a synthetic opiate medication, blocks the effects of heroin its results are encouraging. 

Camacho A, Matthews SC, Dimsdale JE. Invisible synthetic opiates and acute psychosis. N Engl J Med 2001 345(6) 469. 

One of the commonest drugs usL d to treat intestinal cramps and diarrhea is Lomotil, a combination of a synthetic opiate called diphenoxylate and atropine, one ot the constituents of nigiushade plants. Both of these drugs reduce the movement of the intestines by paralyzing the nerves that control them. Diphenoxylate is a close chemical relative of meperidine (Demerol), one of the strong medical narcotics. Like its relative, diphenoxylate can cause depression ot the nervous system that may he intensified by simultaneous use of other depressants. It can also cause euphoria and dependence. Many patients who take Lomotil for intestinal upset experience narcotic effects on mood but have no idea they are using an opiate. 

Chemical/Pharmaceutical/Other Class Synthetic opiate agonist and antagonist... 

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