Metformin is a commonly prescribed drug used to treat type 2 diabetes. The drug works by decreasing the amount of glucose the liver produces, increasing the sensitivity of muscle cells to insulin, and delaying the absorption of glucose in the intestines. Approximately 50% - 55% of metformin is absorbed in the small intestines. Most of the drug is excreted in the urine, so a patient with renal impairment may need a lower dose of the drug. Common side effects include nausea, vomiting, and diarrhea. Metformin may increase the risk of vitamin B12 deficiency. A rare but serious complication of metformin treatment is lactic acidosis, which is characterized by a blood pH of less than 7.35 and a plasma lactate concentration of greater than 5.0 mmol/L. The risk of lactic acidosis increases with the dose of metformin. The current recommended maximum dose of metformin is 2.0 g per day.
KeywordsDiabetesMetforminPharmacokineticPharmacodynamicPersonalized Medicine
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