Oxymorphazone Properties

Description

Oxymorphazone is an opioid analgesic drug related to oxymorphone. It is a potent and long acting ?-opioid agonist which binds irreversibly to the receptor, forming a covalent bond which prevents it from detaching once bound. 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. However with repeated doses, tolerance to the effects develops rapidly, as chronically activated opioid receptors are rapidly internalised by β-arrestins, in a similar manner as occurs with non-covalent binding by agonists with extremely high binding affinity such as lofentanil.