Oxymorphazone is an opioidanalgesic drug related to oxymorphone. Oxymorphazone is a potent and long acting μ-opioidagonist which binds irreversibly to the receptor, forming a covalent bond which prevents it from detaching once bound.[1][2] This gives it an unusual pharmacological profile, and while oxymorphazone is only around half the potency of oxymorphone, with higher doses the analgesic effect becomes extremely long lasting, with a duration of up to 48 hours.[3] However, tolerance to analgesia develops rapidly with repeated doses,[4][5][6] as chronically activated opioid receptors are rapidly internalised by β-arrestins, similar to the results of non-covalent binding by repeated doses of agonists with extremely high binding affinity such as lofentanil.[7][8]
^Galetta S, Ling GS, Wolfin L, Pasternak GW (1982). "Receptor binding and analgesic properties of oxymorphazone". Life Sciences. 31 (12–13): 1389–92. doi:10.1016/0024-3205(82)90388-5. PMID6183551.
^Williams CL, Bodnar RJ, Clark JE, Hahn EF, Burks TF, Pasternak GW (April 1988). "Irreversible opiate agonists and antagonists. IV. Analgesic actions of 14-hydroxydihydromorphinone hydrazones". The Journal of Pharmacology and Experimental Therapeutics. 245 (1): 8–12. PMID2452249.
^Benyhe S, Hoffmann G, Varga E, Hosztafi S, Toth G, Borsodi A, Wollemann M (1989). "Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro". Life Sciences. 44 (24): 1847–57. doi:10.1016/0024-3205(89)90302-0. PMID2472540.
^Marie N, Aguila B, Allouche S (November 2006). "Tracking the opioid receptors on the way of desensitization". Cellular Signalling. 18 (11): 1815–33. doi:10.1016/j.cellsig.2006.03.015. PMID16750901.
^DuPen A, Shen D, Ersek M (September 2007). "Mechanisms of opioid-induced tolerance and hyperalgesia". Pain Management Nursing. 8 (3): 113–21. doi:10.1016/j.pmn.2007.02.004. PMID17723928.