GLP-1 (Glucagon-Like Peptide-1) and GIP (Glucose-Dependent Insulinotropic Polypeptide)/GLP-1 Receptor Agonists for Antipsychotic-Induced Weight Gain: A Narrative Review.

The clinical management of severe mental illness faces a profound longevity crisis, as second-generation antipsychotics, particularly clozapine and olanzapine, trigger severe weight gain and cardiometabolic complications that reduce life expectancy by 10 to 20 years. Traditional lifestyle modifications and metformin frequently fail because they do not address the hypothalamic disruption and altered reward signaling caused by these medications. This narrative review synthesizes evidence on advanced incretin-based therapies as a novel counter-regulatory strategy. Glucagon-like peptide-1 receptor agonists, specifically semaglutide, have established a robust benchmark, demonstrating significant weight reduction and cardiovascular risk mitigation in psychiatric cohorts without compromising mental stability. Furthermore, the dual-receptor agonist tirzepatide represents a major paradigm shift, leveraging dual-receptor synergy to provide superior weight loss, optimize adipose tissue function, and reduce hepatic steatosis. Although large-scale randomized controlled trials for tirzepatide in severe mental illness are still limited, preliminary data underscore its extensive role as a comprehensive metabolic stabilizer. Ultimately, closing the mortality gap in psychiatry requires a transition from reactive rescue models toward early, proactive metabolic protection at the onset of antipsychotic therapy.