phenazocine

Phenazocine is a potent opioid analgesic of the benzomorphan class developed in the 1950s as part of efforts to find strong non-addictive painkillers. It is structurally related to pentazocine but exhibits greater potency and fewer side effects due to a more favorable μ/κ-opioid receptor binding ratio. Its mechanism of action involves agonism at the μ-opioid receptor (producing analgesia and euphoria) and activity at κ-opioid and σ receptors (which may cause dysphoria or hallucinations at high doses). The N-phenethyl substitution enhances its μ-opioid activity. Unlike morphine, phenazocine does not induce spasm of the sphincter of Oddi, making it preferable for biliary or pancreatic pain. The drug was once widely used under brand names such as Prinadol and Narphen but has been discontinued in many markets; it remains a Schedule II controlled substance in the United States[1][3][5].

Brand names

PrinadolNarphen

Other names

FenazocinaPhenazocinumPhenethylazocinePhenobenzorphan