Patient's question:
Hello, I went to the bathroom at 8 a.m. this morning and noticed that my stool was very dark, like tar color. Recently, I've been feeling down and have been drinking beer. One day, I even got drunk. Do you think it could be gastrointestinal bleeding? However, I don't have any stomach pain. Could you tell me what are the symptoms of gastrointestinal bleeding?Doctor's answer:
Hello, the iron in hemoglobin, under the effect of gastric acid and intestinal bacteria, reacts with sulfides to form iron sulfide. This compound turns the stool black. Its appearance and color resemble tar, hence it is called tar-like stool. When upper gastrointestinal bleeding is less than 50 milliliters, black stool may reappear. Additionally, taking medications containing bismuth and the blood of animals during defecation can also cause black stool. It is important to distinguish this from upper gastrointestinal bleeding. Due to the large amount of upper gastrointestinal bleeding, it is believed that avoiding cold and stimulating foods can definitely drive away gastric bleeding.