There are more types of bismuth-based gastric drugs, and the common ones are bismuth potassium citrate, bismuth pectin and so on. Bismuth is mainly used in the treatment of chronic gastritis and peptic ulcer, etc. It can not only protect the gastric mucosa, but also play a role in killing Helicobacter pylori. In H. pylori-associated gastritis or gastric ulcer, bismuth is often combined with 2 antibiotics and 1 proton pump inhibitor to form a quadruple regimen, such as bismuth potassium citrate, omeprazole, amoxicillin, and clarithromycin. After taking bismuth, darkening of the tongue and feces can occur, which can be relieved after stopping the medication. Adverse reactions such as nausea and constipation may occur. It is forbidden for patients with severe kidney disease, pregnant women and those who are allergic to the drug. It is also important to note that you should not take more than one type of bismuth at the same time, and you should not take bismuth with milk and antacids. The above medication should be taken under the guidance of a doctor, avoid self-medication.