Patients suffering from polycystic ovary syndrome combined with diabetes mellitus taking too much metformin is usually not good, it may cause lactic acidosis, gastrointestinal adverse reactions, etc. It is not recommended to take too much metformin, and you should follow the doctor’s instructions to take the appropriate dose of the drug. Metformin belongs to the biguanide class of hypoglycemic drugs, can be used to treat patients with type 2 diabetes who cannot control their blood sugar well by diet or exercise alone. And, adverse reactions such as nausea, vomiting, diarrhea, loss of appetite and hypoglycemia may occur after taking metformin. If patients with polycystic ovary syndrome combined with diabetes mellitus take metformin overdose may induce lactic acidosis, which is manifested as drowsiness, confusion, thirst, diarrhea, etc., and they need to go to the hospital immediately for treatment such as gastric lavage and inducing vomiting. Patients with polycystic ovary syndrome combined with diabetes mellitus should follow the doctor’s instructions to standardize the use of medication in daily life, and should not increase or decrease the dosage of medication on their own, so as to avoid triggering adverse consequences.