Melena
It isn’t uncommon for blood to come from the upper gastrointestinal tract, like the stomach or esophagus, to darken stools and turn them black. It’s a condition that’s referred to as melena. People who have melena may notice that their excrement has tarry textures similar to things like coffee grounds. This is because blood tends to change to a darker color as it goes through the body and interacts with the enzymes that aid in food digestion in the gastrointestinal tract. As a result, it can make it more challenging to tell whether or not the stool has blood.
On the other hand, if red blood is found on or in the black stool, it can be surmised that it’s from the GI tract’s lower part, such as the rectum or colon. Blood from these regions generally appears redder because it isn’t exposed to most of the body’s digestive process. Moreover, if the dark stool looks tarry and other symptoms like pain, dizziness, vomiting or fainting exist, a doctor should be immediately consulted, as it may be a severe medical emergency.
