3-Methylfentanyl
3-Methylfentanyl (3-MF, mefentanyl) is an opioid analgesic that is an analogue of fentanyl. 3-Methylfentanyl is one of the most potent drugs that has been widely sold on the black market, estimated to be between 400-6000 times stronger than morphine depending on which isomer is used (with the cis isomers being the more potent one).
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