Does peptic ulcer cause black stools?

Blood from a stomach or duodenal ulcer can be digested as it moves through the bowel. This may make stool very dark, sticky, and tar-like, sometimes with a strong odour. The medical term for this appearance is melaena.

Not every dark stool is caused by bleeding. Iron supplements, bismuth-containing medicines, and some foods can darken stool. However, a new black tar-like stool should be treated as potentially serious until a clinician has assessed it; colour alone cannot safely establish the cause.

Contact urgent medical services or seek same-day medical assessment for black tar-like stool, particularly if it is new or repeated. Tell the clinician about any ulcer history, medicines such as anti-inflammatory pain relievers or blood thinners, alcohol use, and recent vomiting. Do not take medicines intended to mask the symptom before getting advice.

Assessment may include checking your pulse and blood pressure, blood tests, and an examination of the upper digestive tract to find and treat a source of bleeding.

Call emergency services immediately if black stools occur with fainting, marked weakness, confusion, shortness of breath, chest discomfort, vomiting blood, or severe abdominal pain. These signs can accompany significant blood loss or another emergency.

Could this stool appearance represent digestive bleeding? Do any of my current medicines increase bleeding risk? Do I need urgent tests, and which symptoms mean I should call emergency services rather than wait for an appointment?