Novel pharmacotherapies for opioid use disorder and opioid withdrawal

Opioid use disorder (OUD) remains a major public health crisis despite evidence-based medications, including methadone, buprenorphine, and naltrexone. Persistent challenges with treatment retention, access, stigma, and incomplete response highlight the need for adjunctive pharmacotherapies targeting neurobiological systems beyond the mu-opioid receptor.

We conducted a narrative review of emerging pharmacologic approaches for OUD and opioid withdrawal syndrome, focusing on ketamine and NMDA receptor antagonists, cannabinoids, psychedelics, and incretin-based therapies, including glucagon-like peptide-1 receptor agonists and dual glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonists.

Ketamine has preliminary randomized evidence suggesting potential effects on abstinence, withdrawal, craving, and psychotherapy augmentation. Cannabidiol may reduce cue-induced craving and anxiety, whereas dronabinol may modestly suppress opioid withdrawal symptoms. Psychedelic research, particularly involving ibogaine, shows observational signals for withdrawal reduction and abstinence but is limited by safety concerns, regulatory barriers, and sparse controlled evidence. Incretin-based therapies have generated strong observational signals linking GLP-1-based treatment to reduced overdose and OUD-related outcomes, though prospective trials remain limited.

Across these therapeutic classes, convergent mechanisms include modulation of mesolimbic reward circuitry, cue-reactivity, stress responsivity, neuroplasticity, and cognitive flexibility. Future studies should prioritize rigorous blinding assessment, active comparators, objective endpoints, standardized cue-reactivity measures, diverse samples, and careful safety monitoring. Regulatory policies should facilitate the development and implementation of future research in novel therapies for OUD.