What is the reason for the black smell?

Black and smelly stools are mainly related to dietary factors, drug factors, disease factors, etc.

1. Dietary factors: If the patient usually ingests iron-rich foods, such as pig blood, duck blood, etc., iron sulfide will be produced in the process of digestion in the intestinal tract, so black and smelly stools will occur.

2. Drug factors: If the patient is taking iron, bismuth and traditional Chinese medicine prescriptions in the near future, the drug metabolism and stool can also cause black and smelly stools.

3. Disease factors: When the patient has peptic ulcer, esophageal and gastric varices and other diseases, it is easy to cause upper gastrointestinal bleeding, and the blood will stay in the intestinal tract for too long, resulting in black and smelly stools.