Normal people taking metformin generally does not cause hypoglycemia, but it is not recommended for normal people to take the drug arbitrarily, the drug needs to be taken under the guidance of a doctor. Metformin mainly reduces blood glucose by inhibiting hepatic glycogen isomerization, reducing hepatic glucose output, increasing the uptake and utilization of glucose by muscle and adipose tissue, and delaying and inhibiting the absorption of glucose in the intestine. Metformin is mainly used for the treatment of type 2 diabetes mellitus, which is more suitable for overweight or obese type 2 diabetic patients because of its weight reduction effect, and can also be used for type 1 diabetic patients with large fluctuation of blood glucose after the application of insulin. The drug is not recommended for normal people. Common adverse reactions to metformin include gastrointestinal reactions, skin allergies and lactic acidosis, and it is contraindicated in patients with severe complications, alcoholism, and severe renal insufficiency. The medication should be used in strict accordance with medical advice.