Tags: Chemical Compound, Chemical Substance.
Morphine-6-glucuronide (M6G) is a major active metabolite of morphine and as such is the molecule responsible for much of the pain-relieving effects of morphine (and thus heroin)[citation needed]. M6G is formed from morphine by the enzyme UDP-Glucuronosyltransferase-2B7 (UGT2B7). M6G can accumulate to toxic levels in kidney failure.