metformina

Metformina, known in English as metformin, is an oral antihyperglycemic agent of the biguanide class used to improve glycemic control in type 2 diabetes. It is commonly prescribed as a first-line therapy alongside lifestyle changes and is suitable for adults and certain pediatric patients. In addition to diabetes, metformina is used in some contexts to treat insulin resistance in polycystic ovary syndrome and may be considered for other off-label indications where appropriate.

The primary mechanism of action is to decrease hepatic glucose production and to improve insulin sensitivity in muscle and adipose tissue, with a relatively limited effect on pancreatic insulin secretion. The drug does not undergo significant metabolism and is excreted unchanged by the kidneys. Activation of AMP-activated protein kinase (AMPK) is thought to contribute to its effects.

Metformina is available in immediate-release and extended-release formulations. It is generally taken with meals to reduce gastrointestinal side effects, and dosing often requires adjustment in the presence of renal impairment. The drug’s pharmacokinetic profile includes absorption from the gut and renal elimination, with a half-life appropriate for once- or twice-daily dosing depending on the formulation.

Adverse effects are most commonly gastrointestinal, including nausea, diarrhea, and abdominal discomfort. A rare but serious risk is lactic acidosis, which is more likely with significant renal impairment, hepatic disease, hypoxia, or dehydration. Long-term use may lower vitamin B12 levels. Contraindications include significant renal impairment, acute metabolic acidosis, and hypersensitivity to metformina.