Question: Can Swallowing Blood From A Nosebleed Cause Black Stool?
Answer: It is not a common reason for black stools (or melena), but swallowing blood after a nosebleed can result in dark stools.
A nosebleed, or epistaxis, is a common occurrence, especially in children between the ages of 2 and 10 and adults between the ages of 50 and 80. Most nosebleeds are not serious, and while they can be recurrent, they typically are treatable at home. Nose-picking; trauma to the nose; and dry, warm air that dries out the mucus membranes are common reasons for nosebleeds.
Most nosebleeds originate in the front of the nasal cavity and are called anterior epistaxis. This causes the blood to drip out of the nose. A nosebleed from the back of the nasal cavity, or posterior epistaxis, is more serious. Posterior epistaxis may produce bleeding from the front of the nose, but it can also occur without any visible blood, which may make it difficult to diagnose. Posterior epistaxis could cause significant bleeding, which puts a patient at risk for anemia, black stools, and even aspiration of blood.
Recurring black stools, especially those that smell foul, should be investigated by a physician. It could indicate bleeding in the gastrointestinal tract and may require treatment.
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