Why does the stool turn black?
When blood enters the lumen of the stomach or duodenum, hemoglobin, under the influence of hydrochloric acid and intestinal bacteria, is converted into hydrochloric acid hematin, a black substance. While the blood passes all the way through the intestines, it has time to completely change, so the stool becomes not red, but coal-black, shiny and sticky, with a characteristic fetid odor. The higher the source is and the slower the content moves, the more typical the picture. With very heavy bleeding from the upper sections, the stool may be dark cherry-colored.
- The source is usually above the ligament, that is, in the esophagus, stomach or duodenum
- The stool is black, sticky, shiny, with a pungent odor
- Scarlet blood in the stool more often indicates the lower parts
- Melena may persist for several days after bleeding has stopped.
Main reasons
The first place is occupied by peptic ulcer of the stomach and duodenum, especially against the background of H. pylori infection and the use of non-steroidal anti-inflammatory drugs. The second most common source is erosion of the gastric mucosa, including after taking painkillers and alcohol. In people with cirrhosis of the liver, bleeding may come from varices of the esophagus, and it can be massive. Less commonly, the cause is rupture of the mucosa with severe vomiting, tumors of the stomach and esophagus, and vascular abnormalities of the intestine.
- Stomach and duodenal ulcers
- Erosion of the gastric mucosa
- Varicose veins of the esophagus with cirrhosis
- Rupture of the mucous membrane due to persistent vomiting
- Tumors of the stomach and esophagus
- Taking blood thinners
When black stool is not dangerous
Dark stools are often the result of diet or medications. Iron supplements make stool almost black, but usually shaped and without shine or foul odor. Activated carbon and bismuth preparations also work. Among the foods that change color are beets, blueberries, blackberries, chokeberries, prunes, and blood sausage. The absence of weakness, dizziness, abdominal pain and normal blood counts help to distinguish these situations. If there is even the slightest doubt, it is safer to consider the stool as melena and seek help.
- Iron supplements
- Activated carbon and bismuth preparations
- Beetroot, blueberry, chokeberry
- Prunes and blood sausage
- The chair is decorated, without shine or strong odor
- Feeling normal, no weakness or pallor
What to do immediately
Black, tarry stools are a reason to seek medical help on the same day, and if you feel weak, dizzy, pale or vomiting blood, call 103 for help. Before being examined by a doctor, you should not eat or drink, take painkillers from the group of non-steroidal anti-inflammatory drugs and alcohol. No need to put a heating pad on your stomach. If a person is taking blood thinners, be sure to tell your doctor, but do not stop taking them yourself. It is useful to remember exactly when such a stool appeared and how many times.
- Get help the same day
- For weakness and fainting - call 103
- Do not eat or drink until the examination
- Do not take painkillers or alcohol
- Don't warm your stomach
- Tell your doctor about all medications you are taking.
Examination and treatment
The main method is endoscopy of the upper digestive tract: it finds the source and allows you to stop the bleeding right during the procedure using clips, coagulation or drug administration. At the same time, a complete blood count, coagulation parameters, and blood group are assessed. In case of significant blood loss, the volume of fluid is replenished, and blood components are transfused if necessary. After stopping the bleeding, drugs that reduce acidity are prescribed, H. pylori is treated, pain relief therapy is reviewed, and in case of cirrhosis, recurrent bleeding is prevented.
- EGD in the first hours after treatment
- Complete blood count and coagulation parameters
- Endoscopic bleeding control
- Proton pump inhibitors
- Eradication of H. pylori in ulcers
- Review of painkillers and anticoagulants
