Oral hypoglycemic agents are an important method of treating diabetes mellitus, and biguanide preparations are the most commonly used oral hypoglycemic agents for patients with diabetes mellitus. The most common side effects of biguanide hypoglycemic agents mainly include the following: i. Gastrointestinal reactions, biguanide preparations can cause nausea, vomiting, epigastric discomfort and other symptoms, and they can be taken after a meal to minimize gastrointestinal tract irritation. Second, weight loss, biguanide preparations can improve insulin resistance, help obese diabetic patients to control their weight, on the wasting patients can also lead to continued weight loss. Third, lactic acidosis, biguanide glucose-lowering drugs play a role by increasing anaerobic fermentation, lactic acid is a product of anaerobic fermentation, in patients with cardiopulmonary insufficiency is prone to lactic acid accumulation, lactic acidosis. Fourth, hepatic and renal impairment, bisabolol preparations do not have significant hepatic and renal side effects, but patients with hepatic and renal insufficiency should be used with caution to avoid aggravating the damage. Fifth, drug allergy, a few patients may have skin itching and rash after taking bimatoprost preparations.