Black stool can be a sign of cancer

Variations in stool color and shape do not necessarily indicate a serious condition. However, it cannot be denied that stool discoloration to black is often a cause for concern. What's more, dark stool can be a symptom of indigestion.

Black stools can be caused by a number of factors, ranging from changes in diet, consumption of certain substances, to bleeding in the digestive system. What is the difference and when should you go to the doctor? Check out the following reviews to find out the answer.

The cause of black stool

Stool color is basically influenced by food and how much bile is contained in it. In addition, one more component that determines the color of stool is bilirubin, which is the pigment (coloring agent) produced by the liver.

Bilirubin is formed from the breakdown of old red blood cells. This pigment then empties into the intestine and interacts with various substances. When the bilirubin in the blood interacts with iron, it turns brownish in color.

However, this brown color can turn black when you consume a substance in large quantities or experience a disease in the digestive system. The mechanism is as follows.

1. Take food or supplements

In healthy people, black bowel movements are usually the result of consuming certain foods, medications, or iron supplements. This is why anemia sufferers who regularly take iron supplements often experience it.

In addition, foods and medicines that often make stools black include:

• blueberries and blackberry,
• Grape,
• beets,
• black licorice,
• chocolate, and
• medication containing bismuth.

If your stool is black and you can remember the food, supplement, or medication that caused it, this is not a big problem. The black color will disappear once you stop consuming the substance.

However, if your stool turns black for no apparent reason, you need to see if there is blood in your stool. Another characteristic that indicates a problem with the digestive system is the smell of feces that is more pungent than usual.

2. Indigestion

If the black color of the stool is not related to food, medicine, or iron supplements, the cause is probably bleeding in the upper digestive tract such as the stomach and esophagus. This condition is known as melena.

Bleeding generally begins with the formation of a wound on the wall of the esophagus, stomach, or small intestine. In certain cases, bleeding can also be caused by swollen and eroded blood vessels by digested food.

Please note that melena is different from bloody bowel movements, aka hematochezia. Hematochezia is a condition when the stool comes out with fresh blood. This indicates that bleeding occurs in the lower digestive tract such as the large intestine, rectum, or anus.

Meanwhile, melena occurs due to bleeding that is located far from the anus. Blood from the upper digestive tract interacts with digestive enzymes and undergoes oxidation. This process eventually turns the blood black.

Here are some health problems that often cause melena.

• Ulcers in the stomach or intestines resulting in the formation of sores.
• Gastritis or inflammation of the stomach wall.
• Esophagitis or inflammation of the esophagus.
• Gastroesophageal reflux disease (GERD) or acid reflux disease.
• Diseases that cause inflammation of the intestines, such as celiac disease and Crohn's disease.
• Tumors of the upper gastrointestinal tract.
• Swelling of blood vessels in the upper digestive tract.
• Cirrhosis of the liver.
• Increased pressure of the vessels of the liver.
• Diseases that cause excessive bleeding such as hemophilia, thrombocytopenia, and so on.

When should you see a doctor?

Stool discoloration to black is basically an emergency condition that requires medical attention. When you have melena, you may also experience other symptoms due to blood loss, such as:

• anemia,
• shock,
• pale skin,
• limp body,
• hard to breathe,
• stomach ache,
• dizziness and lightheadedness, and
• increased heart rate.

Melena accompanied by shock should also be treated immediately because this indicates that bleeding is still occurring. If you experience this condition, seek emergency help immediately to get proper treatment.

How to deal with black stool

Doctors first need to diagnose the cause of melena in order to determine its treatment. The diagnosis process begins with studying your medical history, including whether you are taking non-steroidal pain medications that can irritate the stomach.

After that, the doctor will perform a number of examinations, among them nasogastric lavage to measure the amount of blood lost. This procedure also prepares the patient for upper gastrointestinal endoscopy.

Apart from endoscopy, other tests that may be done are complete blood count, x-rays such as barium enema, and colonoscopy. Doctors often also perform stool examinations to confirm a diagnosis.

Once the cause is identified, the new doctor can suggest treatment options. The following treatment options may be offered.

• Injection of drugs to stimulate blood clots in the gastrointestinal tract during endoscopy.
• Cauterization, which is the technique of closing a wound by burning it using low-voltage electricity. This procedure is also performed during the endoscopy.
• Cover the wound using a clamp or tie. This method aims to remove swollen blood vessels.
• Installation of a special catheter to block blood flow in the bleeding tissue.
• Take medicine proton pump inhibitor to stimulate healing of gastric ulcers and stop bleeding.
• Antibiotics to treat bleeding due to bacterial infection H. pylori.
• Blood transfusion if the bleeding is very severe or doesn't stop.

Melena can last up to five days after the bleeding has finished, depending on how severe the bleeding is and how fast your digestive tract moves. Proper handling will help recovery faster.

Stool discoloration to black can be caused by a variety of factors, from consumption of food and supplements to indigestion. When the discoloration of the stool is caused by gastrointestinal bleeding, the condition is called melena.

The color of the stool will return to normal after you stop consuming the substance that causes it. However, discoloration of stool due to indigestion needs medical attention as soon as possible.