Chronic colitis has a long course and tends to recur, and is an inflammation of the colonic mucosa due to a variety of causes. The inflammation more often involves the sigmoid colon and rectum. Diarrhea is the most common manifestation of colitis. The number of bowel movements increases from 2-4 times a day in patients with mild disease to more than 10 times a day in patients with severe disease. The nature of the stool varies from dilute watery stool, mucus stool, pus and blood stool, to blood stool, depending on the degree of mucosal lesions. The frequency also varies. The number of stools varies from one to dozens of times a day. Chronic colitis can also present with varying degrees of abdominal pain, usually located in the lower abdomen, especially the left lower abdomen, varying in severity, and usually disappearing after a bowel movement. Other symptoms may include abdominal distension, loss of appetite, nausea and vomiting, wasting, and weakness, etc. It can also be complicated by multiple other systems and diseases. If the lesion often reaches the rectum, there is a feeling of urgency and heaviness. The disease can be seen at any age and is prolonged. It requires active lifestyle management, a light diet, avoidance of stimulating foods, no milk, no tolerated foods, adequate rest and sleep, and a good state of mind are very important, and active cooperation with the doctor’s treatment.