Dark, unshaped stools may be related to diet, drug factors, may also be caused by gastrointestinal bleeding or blood disorders, as follows: 1, stool color is closely related to diet, animal liver, animal blood, spinach, prunes, mulberries and other foods rich in iron, can be combined with sulfide in the intestine to form iron sulfide, the phenomenon of dark, unshaped stools. 2, drug factors, often taking certain The drugs can also affect the stool, such as iron for blood, bismuth for gastric disease. 3, upper gastrointestinal bleeding, including bleeding caused by esophageal, gastric, duodenal and pancreaticobiliary diseases, of which ulcers are the most common cause of bleeding, usually manifested as vomiting blood and black stools, accompanied by distension and pain in the upper abdomen. 4, blood disorders, such as aplastic anemia, neonatal bleeding disorder, allergic purpura, hemophilia, sepsis.