 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.The uses of Tagamet HB Oral: Cimetidine is used to treat ulcers of the stomach and intestines and prevent them from coming back after they have healed. This medication is also used to treat certain stomach and throat (esophagus) problems caused by too much stomach acid (such as Zollinger-Ellison syndrome, erosive esophagitis) or a backward flow of stomach acid into the esophagus (acid reflux disease/GERD). Decreasing extra stomach acid can help relieve symptoms such as stomach pain, heartburn, difficulty swallowing, cough, and trouble sleeping. It can also prevent serious acid damage to your digestive system (such as ulcers, cancer of the esophagus).Cimetidine belongs to a class of drugs commonly called H2 blockers. It works by reducing the amount of acid in your stomach.This medication is also available without a prescription. It is used to treat occasional heartburn caused by too much acid in the stomach (also called acid indigestion or sour stomach). It is also used to prevent heartburn and acid indigestion caused by certain foods and beverages. </s>