Melena vs hematochezia symptoms and differences GASTROINTESTINAL HEMORRHAGE (2): Melena. Melena, the passage of black, tarry stools, usually implies blood loss greater than 500 ml originating anywhere between the oropharynx and the right hemicolon. Melena occurs most often, Retroflexions.com The Rectal Bleeding Rainbow Having melena in stool makes it Melenic Stool NOT Melanotic stool MELENIC MELANOTIC #MedTwitter #IMbound #EMbound #MedEd #GITwitter Foods That Cause Dark Stools and When to Be Concerned GoodRx What Does The Color Of Your Stool Tell You