Like anal fissures ... when they're sitting inside the digestive tract. This blood might also make your stool look darker than usual. Constipation is the most common cause of bloody diarrhea ...

If you’ve taken bismuth medication like Pepto Bismol, that can also make your stools look almost black. It’s always best to check with a doctor if you’re unsure. Bright red blood in your stools If you ...

Colorectal cancer can seem a lot like some common gastrointestinal ... and make your stool look bloody or black. You could also see blood in the toilet or on tissue if you have hemorrhoids ...