What is black stool called?

Melaena describes stool that becomes dark, sticky, and tar-like after blood is altered by digestion. It is a description of an appearance, not a diagnosis. Causes can include gastritis, a peptic ulcer, or Helicobacter pylori infection, although dark stool can also follow iron products or strongly coloured foods. A clinician may need the timing, texture, associated symptoms, and medicine history to work out whether the change is likely to represent bleeding.

If you notice a new stool that fits this description, contact a healthcare professional promptly. Record its colour and texture, when it appeared, and whether you have pain, nausea, vomiting, dizziness, or weakness. Mention all medicines and supplements, especially products that affect the stomach or stool colour. Avoid taking extra anti-inflammatory pain medicine without medical advice, and do not postpone assessment because you feel comfortable.

Go to emergency care for melaena with faintness, confusion, severe pain, cold sweats, marked weakness, repeated vomiting, or vomit containing blood or coffee-ground material. Such symptoms may indicate active digestive bleeding. If you are unsure whether the stool is truly tar-like, seek advice when the change is new or repeated rather than trying to diagnose it from colour alone.

Ask whether your stool appearance is consistent with melaena, whether a medicine or food could explain it, and what examination or tests may be needed. Ask whether gastritis, peptic ulcer disease, or Helicobacter pylori infection could be contributing.