Medications are an important adjunct in the treatment of constipation. Common drugs for constipation include laxatives, softeners/lubricants, gastrointestinal power drugs and microecological agents. 1, laxatives: the most commonly used drugs for the treatment of constipation, according to its different mechanisms of action can be divided into volumetric laxatives, osmotic laxatives and stimulating laxatives. The use of laxatives for the treatment of constipation should pay attention to the following points: chronic constipation preferred volumetric laxatives (bulking agent) and osmotic laxatives, only when necessary to use stimulant laxatives; the use of laxatives after the improvement of symptoms should be maintained at the minimum dose or gradually reduce the amount, can not be suddenly stopped; such as more than a week still can not correct constipation, should be carefully looking for the cause of the disease. Common osmotic laxatives are sorbitol and lactulose. These drugs are not absorbed in the intestinal tract, have high permeability, increase the water in the intestinal lumen, stimulate intestinal peristalsis, and can be decomposed and fermented through the role of Escherichia coli to generate lactic acid and other acidic metabolites, with osmotic effect, so that the water in the colon increases, stool softening. Polyethylene glycol 4000 (Fosamax) is a new type of volumetric laxative, some people classify it as osmotic laxative, but in fact, polyethylene glycol in the intestinal tract is to fix water molecules through hydrogen bonding so that the water is retained in the colon to increase the water content of feces, to restore the volume and weight of feces, and to promote the completion of defecation, and does not change the osmolality of the intestinal tract, is not decomposed by the bacterial gas production in the colon, and does not appear to be a cellulose and sugar type laxative may be cause bloating or gastrointestinal flatulence, and does not cause disorders of water and salt metabolism. Lactulose and polyethylene glycol are commonly used anti-diarrheal drugs, clinical application shows that the two are safe and effective in the treatment of chronic constipation. 2, softeners or lubricants: common softeners or lubricants are Kaiser Permanente and paraffin oil. These drugs can stimulate the colon to contract and soften the stool. However, enema caused by reflex defecation is a temporary therapeutic measure, should not be used for a long time, often enema can produce dependence. 3, gastrointestinal power drugs: gastrointestinal power drugs is also an important treatment in the treatment of constipation, the current clinical use of gastrointestinal power drugs mainly for cisapride, by stimulating the intestinal interosseous plexus release of acetylcholine and promote the transverse colon movement increase. However, the selectivity is poor, and it can be tried when other treatments are ineffective, and it is not used as routine medication. 4, microecological agents: on the role of microecological agents on constipation, the more common saying is that the lack of intestinal microorganisms lead to intestinal morphology and functional abnormalities; Lactobacillus acidophilus (acid) or Bifidobacterium acidophilus can shorten the cycle of the aseptic animal migratory motor complex wave, while stimulating the transmission of small intestines; the difference between the healthy individuals and chronic constipation in the intestinal microecology of the patient is mainly the clostridial genera and the number of intestinal bacteria increase. A decrease in the number of Bifidobacteria and Lactobacilli. However, it is not clear whether these ecological dysregulations are secondary to constipation or a contributing factor. Other studies have shown that the addition of Bifidobacterium spp. promotes colonic conductance in both healthy and constipated populations.