Are there any risks in taking metformin?

Metformin can cause a rare but sometimes fatal condition called lactic acidosis. This is more common in people with kidney, liver, or heart problems. This can occur because of metformin causing lactic acid accumulation in the blood of some people, and is fatal in approximately 50 percent of cases. Lactic acidosis occurs in a number of different conditions, including type 2 diabetes. People who drink a lot of alcohol or are elderly may be at higher risk.

Metformin may cause hypoglycemia, which is low blood sugar. Symptoms for hypoglycemia are dizziness, shakiness, irritability, nervousness, changes in mood or behavior, headache, weakness, numbness or tingling around your mouth, hunger, pale skin, and clumsy movements. If you do not get treated for hypoglycemia, it can become more severe and graduate into confusion, followed by seizures and loss of consciousness.

You can also develop hyperglycemia, which is high blood sugar. Symptoms are frequent urination, extreme hunger, thirst, blurred vision, and weakness. If not treated, it can develop into a more serious life-threatening diabetic ketoacidosis. Symptoms are nausea, vomiting, dry mouth, fruity smelling breath, and lapsing in unconsciousness.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.