Opioids totally synthetic

Meperidine hydrochloride (the full name) is a synthetic opioid. It is synthesized by the reaction of chemicals not found in opium. Specifically, meperidine hydrochloride is produced by the reaction of dichlorodi-ethyl methylamine with benzyl cyanide, to produce ethyl l-methyl-4-phenyl-isonipecotate hydrochloride (meperidine s chemical name). Some references to meperidine classify it as a totally synthetic opioid. Semi-synthetic opioids are produced by using one of the opiates as a starting material. Two examples of semi-synthetic opioids are hydrocodone and heroin. Hydrocodone is produced by the chemical modification of codeine, while heroin is made by chemically altering morphine. 

Medical means of getting an addict off morphine allows withdrawal with less drastic symptoms. Methadone, legally administered through drug rehabilitation programs, can be substituted for morphine just as it is for heroin. A totally synthetic opioid, methadone lasts longer within the body than either morphine or heroin. Methadone closely mimics the basic opiate stmcture. 

The term opioids refers to these and other derivatives of naturally occurring opium (eg, morphine, heroin, codeine, and hydrocodone) as well as new, totally synthetic opiate anaiogs (eg, fentanyl, butorphanol, meperidine, and methadone Table 11-43). A wide variety of prescription medications contain opioids, often in combination with aspirin or acetaminophen. Dextromethorphan (see p 183) is an opioid derivative with potent antitussive but no analgesic or addictive properties. Tramadol (Ultram )... 

Levorphanol (trade name in the USA Levo-Dromoran ) is a totally synthetic opioid agonist for parenteral and oral administration. Its potency by parenteral route is four to five times higher than for morphine. Similarly advantageous is its long activity duration (up to eight hours) after oral dosing. 

The second group comprises fully synthetic compounds which often have a totally different chemical structure as compared to the semi-synthetic analogs, but interact with the same opioid receptors and show the same spectrum of analgesia and side-effects as the natural compounds. The older name opiates is still in use to describe both groups... 

The second most common alkaloid in opium is codeine, at 0.5-1% of total mass. Codeine is a weak opioid, and is commonly used as an analgesic, sometimes in combination with acetaminophen. The third most common alkaloid is thebaine, at 0.3-1%. Thebaine has similar chemistry but very different biological effects than morphine or codeine, causing dysphoria and agitation in low doses and seizures in high doses. Thebaine is commonly used as a precursor for synthetic opioids. Papaverine is also about 1% of opium, and is a smooth muscle relaxant with little CNS effect. It should be noted that many specialty varieties of P. somniferum have... 

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