Classification Opioid

1 classification

1.1 endogenous opioids
1.2 opium alkaloids , derivatives

1.2.1 opium alkaloids
1.2.2 esters of morphine
1.2.3 ethers of morphine
1.2.4 semi-synthetic alkaloid derivatives


1.3 synthetic opioids

1.3.1 anilidopiperidines
1.3.2 phenylpiperidines
1.3.3 diphenylpropylamine derivatives
1.3.4 benzomorphan derivatives
1.3.5 oripavine derivatives
1.3.6 morphinan derivatives
1.3.7 others


1.4 allosteric modulators
1.5 opioid antagonists
1.6 tables of opioids

1.6.1 table of morphinan opioids
1.6.2 table of non-morphinan opioids

classification

there number of broad classes of opioids:

natural opiates: alkaloids contained in resin of opium poppy, morphine, codeine, , thebaine, not papaverine , noscapine have different mechanism of action; following considered natural opiates: leaves mitragyna speciosa (also known kratom) contain few naturally-occurring opioids, active via mu- , delta receptors. salvinorin a, found naturally in salvia divinorum plant, kappa-opioid receptor agonist.
esters of morphine opiates: chemically altered more natural semi-synthetics, morphine prodrugs, diacetylmorphine (morphine diacetate; heroin), nicomorphine (morphine dinicotinate), dipropanoylmorphine (morphine dipropionate), desomorphine, acetylpropionylmorphine, dibenzoylmorphine, diacetyldihydromorphine;
semi-synthetic opioids: created either natural opiates or morphine esters, such hydromorphone, hydrocodone, oxycodone, oxymorphone, ethylmorphine , buprenorphine;
fully synthetic opioids: such fentanyl, pethidine, levorphanol, methadone, tramadol, tapentadol, , dextropropoxyphene;
endogenous opioid peptides, produced naturally in body, such endorphins, enkephalins, dynorphins, , endomorphins. morphine, , other opioids, produced in small amounts in body, included in category.

tramadol , tapentadol, act monoamine uptake inhibitors act mild , potent agonists (respectively) of μ-opioid receptor. both drugs produce analgesia when naloxone, opioid antagonist, administered.

some minor opium alkaloids , various substances opioid action found elsewhere, including molecules present in kratom, corydalis, , salvia divinorum plants , species of poppy aside papaver somniferum. there strains produce copious amounts of thebaine, important raw material making many semi-synthetic , synthetic opioids. of of more 120 poppy species, 2 produce morphine.

amongst analgesics there small number of agents act on central nervous system not on opioid receptor system , therefore have none of other (narcotic) qualities of opioids although may produce euphoria relieving pain—a euphoria that, because of way produced, not form basis of habituation, physical dependence, or addiction. foremost amongst these nefopam, orphenadrine, , perhaps phenyltoloxamine or other antihistamines. tricyclic antidepressants have painkilling effect well, re thought indirectly activating endogenous opioid system. paracetamol predominantly centrally acting analgesic (non-narcotic) mediates effect action on descending serotoninergic (5-hydroxy triptaminergic) pathways, increase 5-ht release (which inhibits release of pain mediators). decreases cyclo-oxygenase activity. has been discovered or of therapeutic efficacy of paracetamol due metabolite, am404, enhances release of serotonin , inhibits uptake of anandamide.

other analgesics work peripherally (i.e., not on brain or spinal cord). research starting show morphine , related drugs may indeed have peripheral effects well, such morphine gel working on burns. recent investigations discovered opioid receptors on peripheral sensory neurons. significant fraction (up 60%) of opioid analgesia can mediated such peripheral opioid receptors, particularly in inflammatory conditions such arthritis, traumatic or surgical pain. inflammatory pain blunted endogenous opioid peptides activating peripheral opioid receptors.

it discovered in 1953, humans , animals naturally produce minute amounts of morphine, codeine, , possibly of simpler derivatives heroin , dihydromorphine, in addition endogenous opioid peptides. bacteria capable of producing semi-synthetic opioids such hydromorphone , hydrocodone when living in solution containing morphine or codeine respectively.

many of alkaloids , other derivatives of opium poppy not opioids or narcotics; best example smooth-muscle relaxant papaverine. noscapine marginal case have cns effects not similar morphine, , in category own.

dextromethorphan (the stereoisomer of levomethorphan, semi-synthetic opioid agonist) , metabolite dextrorphan have no opioid analgesic effect @ despite structural similarity other opioids; instead potent nmda antagonists , sigma 1 , 2-receptor agonists , used in many over-the-counter cough suppressants.

salvinorin unique selective, powerful ĸ-opioid receptor agonist. not considered opioid nevertheless, because:

endogenous opioids

opioid-peptides produced in body include:

β-endorphin expressed in pro-opiomelanocortin (pomc) cells in arcuate nucleus, in brainstem , in immune cells, , acts through μ-opioid receptors. β-endorphin has many effects, including on sexual behavior , appetite. β-endorphin secreted circulation pituitary corticotropes , melanotropes. α-neo-endorphin expressed in pomc cells in arcuate nucleus.

met-enkephalin distributed in cns , in immune cells; [met]-enkephalin product of proenkephalin gene, , acts through μ , δ-opioid receptors. leu-enkephalin, product of proenkephalin gene, acts through δ-opioid receptors.

dynorphin acts through κ-opioid receptors, , distributed in cns, including in spinal cord , hypothalamus, including in particular arcuate nucleus , in both oxytocin , vasopressin neurons in supraoptic nucleus.

endomorphin acts through μ-opioid receptors, , more potent other endogenous opioids @ these receptors.

opium alkaloids , derivatives
opium alkaloids

phenanthrenes naturally occurring in (opium):

preparations of mixed opium alkaloids, including papaveretum, still used.

esters of morphine

ethers of morphine

semi-synthetic alkaloid derivatives

synthetic opioids
anilidopiperidines

phenylpiperidines

diphenylpropylamine derivatives

benzomorphan derivatives

oripavine derivatives

morphinan derivatives

others

allosteric modulators

plain allosteric modulators not belong opioids, instead classified opioidergics.

opioid antagonists

tables of opioids
table of morphinan opioids




table of non-morphinan opioids