The main types of drugs for constipation are: 1. Volumetric laxatives, also known as salt laxatives, such as magnesium sulfate, through the absorption of a large amount of water, so that the intestinal content of the volume of the increase in the intestinal mucosa stimulation, enhancement of intestinal peristalsis, and other roles in the bowel movement and defecation. This kind of laxative effect is fast and strong, mainly used to eliminate intestinal poison, or combined with anthelmintic drugs to expel intestinal parasites, but there is a certain degree of toxicity, now rarely used.2. Irritant laxatives, such as guide tablets, castor oil, rhubarb, senna and so on, this kind of laxative effect is more severe, long-term use may cause irreversible damage to the intestinal nervous system.3. Lubricating laxative, also known as stool softeners, such as liquid paraffin, Glycerin suppositories, Keseru, Ma Ren Lunji Pills, Ma Ren Soft Capsules, Qi Rong Lunji Oral Liquid, Rhubarb Bowel Pellets, etc., this kind of medicine has a mild effect, does not cause severe diarrhea, suitable for the elderly, women in labor, high blood pressure, postoperative and hemorrhoidal fistula patients. Therefore, the elderly or frail constipation patients are best to use with moisturizing, tonic effect of proprietary Chinese medicines, even if the Chinese medicine is identified as a solid evidence, should not be used to diarrhea effect is too strong medicine. However, even if you choose this type of medicine should not rely on laxatives to defecate for a long period of time, otherwise, once the medicine is discontinued, defecation may be more difficult.　　It should be reminded that people who often have diarrhea or long-term laxatives will lead to the loss of sodium, potassium, calcium and other ions and vitamins in the body, resulting in electrolyte disorders and vitamin deficiencies, the patient can be guided by a doctor, moderate supplementation of multivitamins and so on.