What should you know about one off black stool?

Iron tablets, bismuth-containing medicines and strongly pigmented foods can darken stool. Bleeding from the stomach or upper bowel can make stool black, sticky and unusually foul-smelling; this is sometimes called melaena. Gastritis and a Peptic Ulcer can irritate or damage the digestive lining, while Helicobacter Pylori Infection is one possible contributor to ulcer disease. Colour alone cannot reliably distinguish harmless darkening from bleeding, so describe the texture, smell and any related symptoms to a clinician.

Think back to recent foods, iron or bismuth medicines, and keep the packaging available. Do not stop a prescribed medicine without medical advice. Contact a healthcare professional promptly if the stool was tar-like, the cause is unclear, or it happens again. Mention abdominal pain, vomiting, dizziness, weakness, alcohol use and medicines such as aspirin or anti-inflammatory painkillers. A clinician may check your vital signs, blood count and digestive tract depending on the history.

Go to emergency care for black tarry stool with dizziness, fainting, weakness, pale or clammy skin, rapid breathing, severe abdominal pain, vomiting blood or vomit that looks like coffee grounds. Seek urgent advice for repeated black stools or any black stool when you take blood-thinning medicine. Do not wait for another bowel movement if you feel unwell.

Could a food or medicine explain the colour, or does it look like melaena? Could Gastritis, a Peptic Ulcer or Helicobacter Pylori Infection be relevant? Which medicines should I avoid until this is clarified?