Chronic constipation has functional and organic etiology. Organic etiology can be caused by gastrointestinal diseases, systemic diseases involving the digestive tract such as diabetes, scleroderma, neurological disorders, etc., many drugs can also cause constipation; specific as follows: 1, intestinal organisms, such as tumors, inflammation, or other causes of intestinal luminal stenosis or obstruction. 2, rectal, anal lesions: rectal prolapse, hemorrhoidal disease, anterior rectal dilatation, puborectal muscle hypertrophy, puborectal separation, pelvic floor disease and so on. 3.Endocrine or metabolic diseases: such as diabetic enteropathy, hypothyroidism, parathyroid disease. 4.Neurological diseases: such as central brain disorders, stroke, multiple sclerosis, spinal cord injury and peripheral neuropathy. 5, Intestinal smooth muscle or neuronal lesions. 6.Colonic neuromuscular lesions: pseudo-intestinal obstruction, congenital megacolon, megarectum, etc. 7.Spiritual and psychological disorders. 8, Pharmacological factors: aluminum antacids, iron, opioids, antidepressants, anti-Parkinson’s disease drugs, calcium channel antagonists, diuretics, and antihistamines.