There is no such thing as “the first medicine for constipation”, there are volumetric laxatives, osmotic laxatives, lubricating laxatives, stimulant laxatives and other medicines to treat constipation, please choose the right medicine under the guidance of your doctor. 1. Volumetric laxatives: can increase the water in the feces, make the feces volume increase, the feces is soft and easy to discharge, suitable for mild constipation patients. Such drugs include wheat fiber, polycarbophil calcium, etc.. 2. Osmotic laxatives: can adsorb water through hypertonic state, increase the volume of feces, and then play a role in relieving constipation, applicable to mild, moderate constipation patients. Such drugs are lactulose, polyethylene glycol and so on. 3. Stimulating laxatives: can play a role in stimulating intestinal secretion and enhance intestinal power. These drugs are senna, bisacodyl and so on. 4. Lubricating laxatives: can play the role of lubrication of the intestinal wall, soften the role of feces, suitable for elderly patients with chronic diseases. Including Kaiser, liquid paraffin and so on. 5. Other drugs: Mosapride, Itopride and other gastric stimulants are suitable for patients with slow-transmission constipation; microecological agents can also play a role in relieving constipation, including bifidobacteria, bacillus licheniformis and so on. Patients who need to use drugs to treat constipation are advised to use drugs under the guidance of a doctor.