Normally, the color of feces can vary from tan to dark brown. The color is imparted to it by the digested particles of food and bile pigments secreted into the intestine from the bile ducts with bile.
The color of feces black is often a sign of a serious pathology of the digestive system, but this is often associated with the use of certain foods and medicines.
Food and Drug Administration
Black feces can appear after eating a number of foods. This is red table beets, prunes, red grapes, blueberries, black currants, pomegranates. A change in the color of feces can be after eating dishes such as sausage, bloodsucker, offal. In this case, stool staining can be observed for two to three days, and this symptom is not accompanied by any other changes in the general condition.
Black stool is usually the result of taking pharmaceutical preparations containing iron, which are widely used to treat anemia, some complex vitamins, preparations containing bismuth (used to treat chronic stomach diseases), and activated charcoal. A number of other drugs can also stain black feces, as you can find out by carefully reading the instructions that came with the drug.
With the appearance of black feces, you need to carefully analyze the diet for the past few days. Black feces as a result of taking food products and medicines does not pose any health hazard and does not require treatment. Within two to three days after the exclusion of the use of these products and pharmaceuticals, the normal color of feces is restored.
Medicines, which contain acetylsalicylic acid, do not stain the feces, but with prolonged use they affect the circulatory system and can provoke black feces as a result of the development of internal bleeding.
Diseases accompanied by the appearance of black feces
It is quite another matter if the feces of black color appeared suddenly and seemingly for no reason. If black stool appears, the causes of this symptom should be sought in the gastrointestinal tract. This clinical symptom indicates gastrointestinal bleeding from the digestive tract, especially its upper sections. Black feces, also called melena, most often occurs with peptic ulcer with localization of an ulcer in the stomach or duodenum, intestinal diseases, varicose veins of the esophagus, and tumors of the stomach. With a bleeding pathological focus located in the intestine below the cecum, the blood is usually red. However, with weak peristalsis, black feces can be even with bleeding from the initial part of the colon.
Stool staining black occurs as a result of the fact that under the influence of hydrochloric acid contained in the gastric juice, red blood hemoglobin is converted to black hemin.
With internal bleeding, in addition to black feces, other typical symptoms appear. With the localization of the process, bloody vomiting often appears in the stomach. In this case, vomit under the influence of gastric juice change and take the form of coffee grounds. The patient has hypotension, dizziness, general weakness. On examination, tachycardia, pallor of the skin and mucous membranes are revealed. With severe bleeding, acute vascular insufficiency syndrome develops, requiring emergency care.
The appearance of black feces, which is accompanied by general weakness, abdominal pain of a different nature and intensity, nausea, vomiting and fever, requires urgent medical advice.