Constipation is a common and complex clinical symptom rather than a disease, which mainly refers to the decrease in the frequency of defecation, the decrease in the volume of feces, the dryness of feces, and the effort of defecation. Must be combined with the nature of feces, my usual defecation habits and defecation with or without difficulty to make the judgment of constipation. If more than 6 months is chronic constipation. Constipation from the etiology can be divided into two categories: organic and functional. (1) Organic lesions of the intestinal canal, such as narrowing or obstruction of the intestinal lumen caused by tumor, inflammation or other reasons. (2) Rectal and anal lesions Intrarectal prolapse, hemorrhoids, anterior rectal dilatation, puborectal muscle hypertrophy, puborectal separation, pelvic floor disease and so on. (3)Endocrine or metabolic diseases Diabetes mellitus, hypothyroidism, parathyroid disease, etc. (4) Systemic diseases Scleroderma, lupus erythematosus, etc. (5) Neurologic diseases Central brain disorders, stroke, multiple sclerosis, spinal cord injury, and peripheral neuropathy, etc. (6) Intestinal smooth muscle or neurogenic lesions. (7) Neuromuscular lesions of the colon Pseudo-intestinal obstruction, congenital megacolon, megarectum, etc. (8)Neuropsychological disorders. (9) Pharmacological factors Iron, opioids, antidepressants, anti-Parkinson’s disease drugs, calcium channel antagonists, diuretics and antihistamines. 2, functional Functional constipation etiology is not clear, its occurrence is related to a variety of factors, including: (1) eating less or food lack of fiber or water, the stimulation of colonic movement is reduced. (2) Interference with normal bowel habits due to stressful work, rapid pace of life, changes in the nature and timing of work, and mental factors. (3) Colonic motility dysfunction, commonly found in irritable bowel syndrome, caused by spasm of the colon and sigmoid colon, in addition to constipation at the same time with abdominal pain or abdominal distension, and some patients may be manifested as constipation and diarrhea alternately. (4) Insufficient tension of abdominal and pelvic muscles, insufficient defecation propulsion, difficult to expel feces from the body. (5) Abuse of laxatives, the formation of drug dependence, resulting in constipation. (6) Elderly and weak, too little activity, intestinal spasm resulting in difficult defecation, or due to colon redundancy. 3.Classification Constipation is mainly divided into two categories according to the pathogenesis: slow transmission type and outlet obstruction type. The prevalence of constipation in the population is as high as 27%, but only a small percentage of constipated people will seek medical attention. Constipation can affect people of all ages. It is more common in women than in men, and more common in the elderly than in the young and middle-aged. Due to the high prevalence and complexity of the causes of constipation, patients often have a lot of frustration, and when constipation is severe, it can affect the quality of life. Constipation is often manifested as: less intention to defecate, also less times; defecation difficult, laborious; defecation is not smooth; dry stool, hard stool, defecation unclean feeling; constipation accompanied by abdominal pain or abdominal discomfort. Some patients are also accompanied by insomnia, irritability, dreamy, depression, anxiety and other mental psychological disorders. Because constipation is a more common symptoms, symptoms vary in severity, most people often do not pay special attention to, that constipation is not a disease, no treatment, but in fact, the harm of constipation is very big. The “alarm” signs of constipation include blood in stool, anemia, weight loss, fever, black stool, abdominal pain and family history of tumor. If there are alarm signs, you should go to the hospital immediately for further examination.