What should you know about dark almost black poop?

Stool can look dark after iron tablets, bismuth-containing remedies, or strongly coloured foods. Melaena, also called tarry stool, is typically black, sticky, and unusually foul-smelling because blood has been digested as it passes through the upper digestive tract. Causes can include gastritis, Helicobacter pylori infection, or a peptic ulcer, although the colour alone cannot identify the cause. A clinician will consider pain, nausea, vomiting, dizziness, medicines, alcohol use, previous ulcers, and whether the change happened once or repeatedly. Do not assume a black stool is harmless if you cannot explain it.

Think back to recent iron, bismuth, dark foods, and medicines such as anti-inflammatory painkillers. Take a clear photo if safe and note the texture, smell, timing, and any related symptoms for a clinician. Contact a medical service promptly if the stool is tar-like, recurs, or has no clear food or medicine explanation. Do not stop a prescribed medicine without advice, but tell the clinician about every prescription, supplement, and over-the-counter product. Avoid taking additional anti-inflammatory painkillers while waiting for guidance.

Seek emergency help for black tarry stool with fainting, marked weakness, confusion, breathlessness, rapid heartbeat, severe abdominal pain, vomiting blood, or vomit that resembles coffee grounds. Urgent assessment is also needed if bleeding is possible and you take a blood thinner. Even without dramatic symptoms, arrange prompt review for unexplained black stool, repeated dark stools, or signs of anaemia such as unusual tiredness and dizziness.

Ask whether the appearance suggests bleeding, whether your medicines could explain the colour, and whether testing is needed. Tell the clinician about abdominal pain, indigestion, vomiting, weight change, previous ulcers, iron or bismuth use, and any blood-thinning medicine.