The side effects of Gevalt, i.e. Metformin Hydrochloride Tablets, are mainly gastrointestinal reactions, such as nausea, vomiting, diarrhea, etc. Some patients will gradually tolerate it, while some will react more heavily and cannot tolerate it, at which time the only way is to stop Metformin and choose other oral hypoglycemic drugs. In order to reduce the adverse reactions in the digestive tract, it can be taken with or after meals, starting with small doses and gradually increasing the dose. In addition, a more serious side effect of metformin is lactic acidosis, but this is very rare. In addition, long-term use of metformin may lead to vitamin B12 deficiency, and vitamin B12 levels should be monitored regularly and supplemented when necessary. Note that patients with hepatic and renal insufficiency and chronic gastrointestinal diseases, pregnant and lactating women, and alcoholics should not use metformin.