Diarrhea with black stools may be caused by bleeding in the upper gastrointestinal tract or by medications or food staining.
The possible causes of diarrhea with black stools are probably reactions to food, medications or staining, or diseases of the digestive tract, but in most cases it may be caused by a disease of the digestive system.
Some common foods in daily life, such as spinach, animal blood products, and offal, which undergo a series of biochemical reactions in the gastrointestinal tract may cause the stool to appear black.
If you have black diarrhea after taking a certain medication, you may have an adverse reaction to the medication or the medication may have injured the gastrointestinal tract and caused gastrointestinal bleeding, so you need to find out the cause and decide whether to stop taking the medication under the guidance of your doctor.
Iron sulfide, formed by the combination of iron in our blood and sulfide in food, makes the stool black, so when bleeding disorders occur in the digestive system, such as gastrointestinal perforation, gastric cancer, esophageal cancer, gastric ulcer, ruptured esophagogastric varices, etc., the blood from the overflowing blood vessels combines with sulfide in the intestines to produce iron sulfide, which also makes the stool black.
So if you have diarrhea and black stool, it is best to go to the hospital to find out the cause, which can be effective in early detection of some diseases and positive for early diagnosis and treatment of diseases.