Metformin is known generically as cimetidine. It has the effect of treating symptoms such as acid reflux and heartburn; adverse reactions such as headache, dizziness, diarrhea, rash, and hair loss may occur with the use of this drug. Cimetidine has the effect of inhibiting the secretion of gastric acid and reducing the basal secretion of gastric acid, and is commonly used clinically for the treatment of excessive secretion of gastric acid due to various causes, and the resulting symptoms of stomach pain, heartburn, and acid reflux. The medication is not recommended to be used for more than 7 days. Adverse reactions such as gynecomastia, decreased libido, diarrhea, dizziness, headache, muscle cramps or pain, rash, hair loss, and other adverse reactions may occur during prolonged or heavy use of the drug. The occurrence of the above symptoms of adverse reactions, it is recommended to go to the hospital, stop continuing the use of the drug and symptomatic treatment, if necessary. The drug is contraindicated in cases of hypersensitivity to the product and the components contained in it, pregnancy, breastfeeding. It is also recommended to use the drug with caution in the presence of severe cardiac impairment, severe respiratory diseases, systemic lupus erythematosus, craniocerebral injuries, hepatic and renal insufficiency, etc. It is not suitable for children under 16 years of age. Cimetidine needs to be used under the guidance of a clinician and unauthorized use is prohibited.