Tannic acid ointment has an astringent effect and is able to precipitate proteins to harden the skin, thus protecting the mucous membranes and reducing painful oozing. Main indications: for decubitus ulcers, eczema, hemorrhoids, newborn diaper rash. Adverse reactions: large areas of use may occur due to wound absorption of viruses on the liver also has a sharp toxicity, serious liver necrosis, and deepen the wound, delaying healing. Tannic acid ointment and heavy metals and proteins have contraindications, but also should avoid contact with iron. The body if there is a disease should first go to the regular hospital to find a doctor for examination, all drugs need to be used under the guidance of a professional doctor, to avoid their own abuse of drugs, so as not to cause adverse reactions.