What is Black Colored Stool (Melena)? Why Does It Happen?

The black color of the stool is often caused by digested blood. Bleeding due to any health problem in the upper gastrointestinal tract causes black stools called melena. A small amount of bleeding may not cause a visible color change in the stool. This condition can only be noticed in stool tests where a stool sample is examined. Unlike this condition, also known as occult blood in the stool, melena has a distinct black color. Black stools due to acute-onset heavy bleeding can be easily noticed by the patient. Since serious blood loss may occur in such a situation, the necessary health checks should be performed by applying to health institutions as soon as possible.

What is Melena?

Melena; It is the name given to abnormal, foul-smelling feces that have a tar-like black color. “What does Melena mean?” The question can also be answered as black colored stool. The black color in question is caused by blood flowing into the digestive cavity as a result of bleeding in the upper gastrointestinal tract. The blood in the digestive system acquires a black, tar-like sticky character as a result of digestion by stomach acid and intestinal enzymes. Most of the bleeding that causes melena is bleeding in the esophagus and stomach. In addition, bleeding from the upper parts of the small and large intestine can also cause melena. In bleeding that occurs in the lower parts of the digestive system, the blood in the stool becomes cherry-colored or bright red because the blood is not sufficiently exposed to enzymes. This condition, which is called blood in the stool, occurs in the anal area; hemorrhoids and anal fissure in the large intestine; It can be caused by different diseases such as ulcers, cancer and polyps.

What Causes Black Stool?

The causes of black stools include many different diseases that can cause bleeding in the upper parts of the gastrointestinal tract. People who encounter such a problem for the first time and have not been diagnosed with any digestive system disease before may ask, “Why is the stool black?”, “What causes black stool?” It frequently seeks answers to questions such as: Some of the situations that may cause black stools can be listed as follows:

• Esophageal Varicose Veins:In some cases, such as cirrhosis, enlargement of the veins in the esophagus may lead to esophageal varicose veins. When these enlarged vessels rupture, serious bleeding may occur. Blood flowing into the esophagus causes black stools as it will be excreted through the feces. There is a high probability of experiencing bloody vomiting (Hematemesis) due to blood excreted through the mouth in addition to the feces.
• Gastritis: Inflammation that occurs in the layer covering the inner surface of the stomach is called gastritis. Acute or chronic gastritis, which can be caused by reasons such as smoking and alcohol use, infection caused by the bacteria called Helicobacter Pylori, and eating unhealthy and excessively spicy foods, can cause mucosal damage and lead to bleeding in the stomach. In this case, black stool problems are likely to occur.
• Esophagitis:An infection in the mucosa layer on the inner surface of the esophagus or erosions and ulcers caused by acid reflux from the stomach to the esophagus can cause bleeding in the esophagus and cause melena.
• Stomach Ulcer:Stomach ulcers, also called peptic ulcers, are sores that form on the inner surface of the stomach. Although the most common cause is infection with the bacteria called Helicobacter Pylori, which also causes gastritis, stomach ulcers that develop due to different reasons can cause serious bleeding if left untreated. This situation also brings about melena.
• Pressure Bleeding:A sudden and severe increase in intra-abdominal pressure due to reasons such as severe retching, vomiting, and coughing may cause rupture in the area where the esophagus meets the stomach and therefore bleeding. Melena is an important finding in this type of bleeding.
• Various Medications:Non-steroidal anti-inflammatory drugs, which are frequently used as painkillers and anti-inflammatory agents, increase the tendency for bleeding in the body. Likewise, medications called blood thinners, anticoagulants or anticoagulants also increase the tendency for bleeding. Due to these, especially in individuals with diseases such as gastritis and stomach ulcers, gastrointestinal bleeding may occur as a result of long-term use of non-steroidal inflammatory drugs or anticoagulant drugs, and in addition, black color may be observed in the stool. If such a situation occurs, a physician should be consulted immediately as the drug may need to be discontinued.
• Gastrointestinal System Cancers:Tumors occurring in the digestive system are another important cause of gastrointestinal system bleeding. In case of bleeding, especially in tumors occurring in the initial part of the intestines, esophagus and stomach, it is possible to see black color in the stool.
• Ingestion of Mother’s Blood in Newborns:It is natural for newborn babies to have black stools in the first few days. This is caused by the baby swallowing the mother’s blood during birth. This condition, which usually improves within a few days, should be consulted with a physician if it continues for a longer period of time.

Which Doctor Should You See If Your Stool Is Black?

It is recommended that people who see themselves having black stool problems should consult a health institution and get checked. In such a case, many people wonder which doctor should be consulted. People with melena complaints should consult gastroenterology specialists serving in gastroenterology outpatient clinics of hospitals.

If a gastroenterologist cannot be reached, you can also apply to internal medicine outpatient clinics to undergo an examination by having tests such as blood tests and stool tests required for preliminary diagnosis. A detailed medical history is first taken from patients applying to a health institution. After obtaining information such as how long the bleeding has been going on, whether there are any other problems such as diarrhea or vomiting, and what medications are used, if any, various diagnostic tests are performed. Routine blood tests, arterial blood gas measurement, and liver function tests are performed to investigate the cause of bleeding. In addition, a stool test is performed to determine whether the black stool is due to bleeding. Gastrointestinal bleeding that continues for a long time usually causes a decrease in hemoglobin and hematocrit levels, resulting in anemia. By examining these parameters in blood tests, it can be determined whether the bleeding is acute or chronic. In addition, the location and exact cause of bleeding can be determined by imaging the esophagus, stomach, small and large intestines with endoscopic methods. Meanwhile, tissue samples obtained by biopsy from problem areas can be sent to pathology units for examination under laboratory conditions. Examinations such as computed tomography performed by administering IV (intravenous) contrast material are also among the screening methods that can be applied depending on the patient’s condition.

After all these procedures, the cause of black stools can be determined exactly. If there is bleeding, its location and cause can be precisely diagnosed. Following the diagnosis of the disease causing melena, a focused treatment plan is created. With treatment, it is possible to eliminate bleeding and return the stool to normal color, as well as to treat other problems caused by bleeding.

If you observe a black or abnormal color in your stool, it is recommended that you consult a health institution to find out the cause of this situation. In case of a possible bleeding, you can prevent health problems due to blood loss by getting treatment early.