3-Methylthiofentanyl is an opioid analgesic and analogue of fentanyl.
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| tradename = | pregnancy_AU = | pregnancy_US = | pregnancy_category = | legal_AU = | legal_BR = F1 | legal_CA = Schedule I | legal_UK = Class A | legal_US = Schedule I | legal_DE = Anlage I | routes_of_administration =
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).