GLP-1 Receptor Agonists in Addiction Psychiatry—Neurobiological Rationale, Emerging Clinical Evidence, and Cautions for Practice: A Narrative Review

Glucagon-like peptide-1 (GLP-1) receptor agonists, originally developed for type 2 diabetes and obesity, have recently attracted interest as potential modulators of addictive behavior. This narrative review summarizes current knowledge on the neurobiological basis, randomized controlled trials, and psychiatric relevance of GLP-1 analogs in substance use disorders. English-language articles available at the time of the search were reviewed between February and April 2026, with emphasis on topics most relevant to psychiatric practice. The literature suggests that GLP-1 signaling influences reward processing, cue reactivity, stress responses, relapse vulnerability, and executive control through actions in the gut–brain axis and mesocorticolimbic circuitry. Early clinical findings are most encouraging in alcohol-related outcomes, including reductions in alcohol cue reactivity, craving, alcohol self-administration, and some measures of heavy drinking, whereas evidence in nicotine dependence is mixed and appears more consistent for limiting post-cessation weight gain than for improving abstinence itself. Evidence for other substance use disorders remains preliminary. Across randomized controlled trials, interpretation is limited by small sample sizes, short follow-up, heterogeneous endpoints, and selective populations. In addition, psychiatric and behavioral safety requires careful attention, particularly regarding rapid weight loss, excessive appetite suppression, restrictive eating, dehydration, and psychological destabilization in vulnerable individuals. At present, GLP-1 receptor agonists should be regarded as promising but unproven adjunctive candidates in addiction psychiatry, warranting further rigorous trials, structured monitoring, and interdisciplinary collaboration.