Black and hard stools, mostly considered constipation. Normal stool should be yellow, soft, and contain a certain amount of water, but patients with constipation will have a grain of stool, black spherical, sheep stool-like performance. The reason is that the food eaten by constipated patients is not excreted in the intestine for a long time, and the stool stays in the intestine for too long, and the water is reabsorbed by the intestine, so that the water in the stool is reduced and the stool becomes dry and forms hard knots. Patients with constipation are advised to adjust their dietary structure and habits, drink more water, eat more fresh vegetables and fruits, eat more laxative and crude fiber-rich foods such as sweet potatoes, bananas, honey water, yogurt, etc., and eat less spicy and stimulating and too finely processed rice and noodles. Every day to develop good bowel habits, regular bowel movements, when there is an intention to go to the toilet in a timely manner. You can also take oral medication to promote gastric power and digestion, and use laxatives and anal plugs as directed by the doctor if constipation is severe.