Benzamide Opioids

Cyclohexyl benzamides — a μ-agonist scaffold that is neither a morphinan nor a piperidine. AH-7921 and the U-series (U-47700, U-49900, U-48800) came out of pharmaceutical research programmes that never brought them to market, and reappeared as research-chemical powders sold under their code names.

None of them has a licensed product, so there is nothing to compare a sample against and no clinical description of an overdose beyond the ordinary μ picture: sedation, pinned pupils, slowed breathing. Members differ by small substitutions that change potency and duration, and they are sold under names separated by a single digit, so the label predicts neither. They are μ agonists, so naloxone should act on them as it does on the rest of this subject — an expectation resting on their mechanism rather than on a body of clinical experience, and one that says nothing about whatever else was in the powder.