Medication
Metformin
What it is
Metformin is a biguanide that reduces hepatic glucose production and improves insulin sensitivity. It has one of the longest safety records of any metabolic medication.
How it is used
Taken orally, usually with food, and often started at a low dose and increased gradually to reduce gastrointestinal upset. Extended-release formulations are frequently better tolerated.
What a provider evaluates first
- Renal function — eGFR determines whether it is appropriate
- HbA1c and fasting glucose
- History of lactic acidosis risk factors, including significant hepatic disease
- Vitamin B12 status, since long-term use is associated with reduced absorption
Considerations and monitoring
- Gastrointestinal upset is the most common reason for discontinuation
- Requires periodic renal function monitoring
- Long-term use may affect vitamin B12 absorption
Questions about metformin
Is metformin a weight-loss medication?
Metformin is not approved for weight management. It is a metabolic medication used primarily in type 2 diabetes and insulin resistance, and providers sometimes use it in metabolic care where the laboratory picture supports it. Any effect on weight is modest compared with GLP-1 therapy. Whether it has a role for you depends on your metabolic markers.
Part of Weight Management.