Etorphine

drugbox

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IUPAC_name = 6,14-endoetheno – 7 a (1-(R)-hydroxy-1 methylbutyl)-tetrahydro-nororipavine
CAS_number = 14521-96-1
legal status =
legal_status = List 1NL Schedule I/II(see text)US
C = 25 | H = 33 | N = 1 | O = 4
molecular_weight = 411.53 g/mol

Etorphine (Immobilon or M99) is a semi-synthetic opioid possessing an analgesic potency approximately 10,000 times that of morphine and was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather in "poppy straw" and in related plants, Papaver orientale and Papaver bracteatum. [ [http://opioids.com/narcotic-drugs/chapter-3.html Opium: the king of narcotics ] ] It was later reproduced in 1963 by a research group at Macfarlan-Smith and Co. in Edinburgh, led by Professor Kenneth Bentley. [Bentley KW, Hardy DG. "New potent analgesics in the morphine series." "Proceedings of the Chemical Society". 1963;220.] [Bentley KW, Hardy DG. "Novel analgesics and molecular rearrangements in the morphine-thebaine group. 3. Alcohols of the 6,14-endo-ethenotetrahydrooripavine series and derived analogs of N-allylnormorphine and -norcodeine." "Journal of the American Chemical Society". 1967 Jun 21;89(13):3281-92. PMID 6042764] It can also be produced from thebaine.

Etorphine is most often used to immobilize elephants and other large mammals. Etorphine is only available legally for veterinary use and is strictly governed by law. Diprenorphine (M5050) is an opioid receptor antagonist that can be administered in proportion to the amount of etorphine used (1.3 times) to reverse its effects. Veterinary-strength etorphine is fatal to humans; one drop on the skin can cause death within a few minutes. [Zoo Vet At Large - Sky Travel (8 July 2007, Part 10 of 26)]

Large Animal Immobilon is a combination of etorphine plus acepromazine maleate. An etorphine antidote Large Animal Revivon contains mainly diprenorphine for animals and a human-specific naloxone-based antidote, which should be prepared prior to the etorphine.

A close relative, dihydroetorphine has been used as an opioid painkiller for human usage in China. It is claimed to be less addictive than traditional opioids but this has yet to be confirmed.

Pharmacology

Etorphine is an agonist at μ, δ, and κ opioid receptors. It also has a weak affinity for the ORL1 nociceptin/orphanin FQ receptor. [Hawkinson JE, Acosta-Burruel M, Espitia SA. "Opioid activity profiles indicate similarities between the nociceptin/orphanin FQ and opioid receptors." "European Journal of Pharmacology". 2000 Feb 18;389(2-3):107-14. PMID 10688973]

Legal status

In Hong Kong, Etorphine is regulated under Schedule 1 of Hong Kong's Chapter 134 "Dangerous Drugs Ordinance". It can only be used legally by health professionals and for university research purposes. The substance can be given by pharmacists under a prescription. Anyone who supplies the substance without prescription can be fined $10000(HKD). The penalty for trafficking or manufacturing the substance is a $5,000,000 (HKD) fine and life imprisonment. Possession of the substance for consumption without license from the Department of Health is illegal with a $1,000,000 (HKD) fine and/or 7 years of jail time.

In the Netherlands, Etorphine is a list I drug of the Opium Law. It is only used for veterinary purposes in zoos to immobilize large animals.

In the US, Etorphine is listed as a Schedule I drug, although Etorphine hydrochloride is classified as Schedule II.

References

External links

* [http://opioids.com/etorphine/immobilon.html Opioids.com] page on etorphine
* [http://www.chm.bris.ac.uk/motm/etorphine/etorphinec.htm Etorphine: Molecule of the Month]