Tag: Black stool

According to manufacturers and medical experts, the dark or black stool commonly experienced after taking Pepto-Bismol is a harmless, temporary side effect. This phenomenon, often referred to as 'Pepto poops,' occurs when the medication's active ingredient, bismuth subsalicylate, reacts with sulfur in the digestive tract.

While roughly 25% of patients on metformin experience some form of gastrointestinal upset, true black, tarry stool (known as melena) is rarely a direct side effect of the medication itself and requires a careful look at other causes. The question, **why is my poop black on metformin?** points toward several potential factors, both harmless and serious, that need to be evaluated.