Black Stools
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Reviewed By:

Aiko Yoshioka

Aiko Yoshioka, MD (Gastroenterology)

Dr. Yoshioka graduated from the Niigata University School of Medicine. He worked as a gastroenterologist at Saiseikai Niigata Hospital and Niigata University Medical & Dental Hospital before serving as the Deputy Chief of Gastroenterology at Tsubame Rosai Hospital and Nagaoka Red Cross Hospital. Dr. Yoshioka joined Saitama Saiseikai Kawaguchi General Hospital as Chief of Gastroenterology in April 2018.

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People with these symptoms also use Ubie's symptom checker to find possible causes

  • Color of stool has become black

  • Poop is black like coal

  • Black shiny stools

  • Black, tarry stool

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Content updated on Jan 4, 2023

About the symptom

Black, shiny stool is also called Malena and is often also described as tarry in texture. It can be caused by bleeding in the gut or taking iron supplements.

When to see a doctor

Seek professional care if you experience any of the following symptoms

  • Fever

  • Dizziness

  • Fainting with loss of consciousness

  • Sickly/pale appearance

  • Vomiting of blood

  • Unexplained weight loss of 5% or more in 1 month

  • Jaundice

  • Edema

  • Recent weight loss

Possible causes

  • Helicobacter pylori infection

    Helicobacter pylori, or H. pylori, is a bacteria commonly found in the stomach of about half the world's population. Most people have no symptoms. However, H. pylori can cause digestive problems, including ulcers and, rarely, stomach cancer. H. pylori bacteria may spread through direct contact with saliva, vomit, feces, or contaminated food or water.

  • Gastroduodenal ulcer

    Ulcers can develop in the stomach and small intestines. In severe cases, the ulcers can cause bleeding or a hole in the gut wall. Common causes include the bacteria H. pylori, and painkillers such as Diclofenac.

  • Meckel's diverticulosis

    Meckel's diverticulum is a congenital bulge in the lower part of the small intestine, which is a remnant of the umbilical cord.

  • Anemia
  • Gastro Esophageal Reflux Disease (GERD)
  • Functional dyspepsia
  • Epistaxis
  • Gastric cancer
  • Candidiasis (oral, hands and feet)

Related serious diseases

  • Ischemic enteritis

    A condition in which the gut wall is damaged due to insufficient blood supply. Causes include low blood pressure, medications, or clots from the heart.

Questions your doctor may ask about this symptom

Your doctor may ask these questions to check for this symptom

  • Do you have stools that are black (like hair) and shiny?

  • Do you have abdominal pain (stomach ache)?

  • Do you have loose stools or diarrhea?

  • Do you have nausea or vomiting?

  • Did you vomit blood?

Other Related Symptoms

Similar symptoms or complaints

Reviewed By:

Aiko Yoshioka

Aiko Yoshioka, MD (Gastroenterology)

Dr. Yoshioka graduated from the Niigata University School of Medicine. He worked as a gastroenterologist at Saiseikai Niigata Hospital and Niigata University Medical & Dental Hospital before serving as the Deputy Chief of Gastroenterology at Tsubame Rosai Hospital and Nagaoka Red Cross Hospital. Dr. Yoshioka joined Saitama Saiseikai Kawaguchi General Hospital as Chief of Gastroenterology in April 2018.

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