Constipation may be related to physiologic causes such as poor defecation habits and poor dietary habits, or it may be related to colorectal and anal diseases such as inflammatory bowel disease and intestinal obstruction. 1. Physiological causes. Constipation can be caused if there are bad defecation habits such as inhibiting the urge to have bowel movements for a long time and taking too long to go to the toilet, as well as bad dietary habits such as drinking too little water and consuming too little dietary fiber. 2. Pathological causes. If you suffer from congenital megacolon, inflammatory bowel disease, hemorrhoids and other colon-anal diseases, it may cause narrowing of intestinal lumen, obstruction and so on, causing constipation. In addition, long-term oral morphine, fluoxetine and other antidepressants, etc., are also prone to cause constipation adverse reactions. When the symptoms of constipation occur for a long period of time, the cause needs to be clarified under the guidance of a doctor so that it can be corrected in time.