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Brands: Glucophage, Glucophage XR, Fortamet, Glumetza
Published 2025-12-23 · Last reviewed 2025-12-30 · 5 references
Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.
Metformin (brand Glucophage; many generics) is a biguanide used for type 2 diabetes. In psychiatry it is commonly used off label to mitigate antipsychotic-associated weight gain and metabolic risk (clinical).
It is generally weight-neutral to modestly weight-lowering and does not typically cause hypoglycemia as monotherapy; GI tolerability and kidney function drive most practical decisions (label/clinical).
The key rare but serious adverse event is lactic acidosis, which is strongly associated with renal dysfunction and other hypoxic states; baseline and periodic kidney-function review is central to safety planning (label).
Evidence syntheses support modest average weight loss and improved metabolic markers in antipsychotic-treated populations, especially when started early after weight gain begins (Wu 2008; Lee 2011).
The metformin compare view, evidence feed, and print page support counseling and coordination with primary care when metabolic adverse effects are driving regimen changes.
In psychiatric practice, metformin is often considered when metabolic monitoring shows weight gain, impaired glucose tolerance, or developing metabolic syndrome during antipsychotic treatment. It is typically used alongside lifestyle interventions and, when feasible, antipsychotic dose/agent adjustments rather than as a stand-alone strategy (clinical).
View labelExactRefer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.
Biguanide antihyperglycemic that reduces hepatic gluconeogenesis and improves peripheral insulin sensitivity (mechanism).
It does not stimulate insulin secretion, so hypoglycemia is uncommon unless combined with insulin or insulin secretagogues (label/clinical).
Metformin is often best coordinated with primary care/endocrinology when diabetes or prediabetes is present, especially when renal function or contrast imaging is in play (clinical).