Lizudra, chemically also known as bismuth potassium citrate. This type of drug is widely used in gastroenterology, on the one hand, mainly for stomach pain, burning sensation and acid reflux caused by excessive stomach acid, or chronic gastritis, gastric ulcer, duodenal ulcer, compound ulcer, etc. On the other hand, it can be used in combination with antibiotics and proton pump inhibitors to eradicate H. pylori infection. When taking such drugs, it is recommended not to use high protein foods, such as milk, at the same time. Darkening of the tongue and feces may occur while taking the drug. Some patients may also experience nausea, vomiting, diarrhea and constipation after oral administration. These drugs are contraindicated in pregnant women, women who are pregnant, and those who are allergic to this type of drug.