What causes black stool?
Disease description:
It started the day before yesterday when I noticed that I had black stools. In addition to the black stools, I also experienced nausea and even passed blood in my stool. What should I do, doctor? What causes black stools?
Doctor's answer (1)
Dr. Shen Yonghua
Common causes of black stool include:
1. Gastrointestinal ulcers: Gastric ulcers or duodenal ulcers are among the most common causes. Damage to the ulcer site can cause blood vessels to rupture and bleed.
2. Gastritis or gastric mucosal lesions: Chronic gastritis or inflammation of the gastric mucosa can make local blood vessels fragile and prone to bleeding.
3. Ruptured esophageal varices: Common in patients with cirrhosis, the veins in the lower esophagus become dilated due to portal hypertension and may rupture, causing massive bleeding.
4. Gastric cancer or gastrointestinal tumors: Malignant tumors in the gastrointestinal tract may erode blood vessels, leading to bleeding.
5. Medications: Certain drugs, such as iron supplements or bismuth preparations, can also cause darkening of the stool. This occurs when these medications combine with sulfides in the intestines to form black-colored sulfides.
6. Dietary factors: Consuming large amounts of iron-rich foods, such as animal liver or spinach, may also darken or blacken the stool.
However, black stool may be a serious symptom of gastrointestinal bleeding, and if left untreated, it can be life-threatening. Therefore, medical evaluation and examination should be sought promptly upon noticing black stool.
