Irritable bowel syndrome has shown good improvement with pivetonium bromide, lactulose, montelukast, and cisapride. Irritable bowel syndrome has a variety of pathogenesis, and there are no new drugs that are definitive and effective in the treatment of irritable bowel syndrome, which is mainly aimed at symptom relief. Pivetonium bromide is a calcium antagonist. When irritable bowel syndrome occurs, the intestine may spasm due to the loss of calcium ions, and the use of pivetonium bromide can relieve intestinal spasm and improve pain, and also help the intestine to restore function and promote recovery. Some cases of irritable bowel syndrome are characterized by constipation and can be treated with lactulose, which balances the intestinal environment, preserves water in the intestinal mucosa, and stimulates peristalsis, allowing fecal matter to be expelled from the intestine. When diarrhea occurs in irritable bowel syndrome, it can be treated with montelukast, which not only has a good antidiarrheal effect, but also does not enter the blood circulation and has fewer side effects. When irritable bowel syndrome is manifested as gastrointestinal motility deficiency, it can be treated with cisapride, which is a full gastrointestinal motility drug that can enhance the peristalsis of the digestive system, help digestion of food, and also prevent reflux of gastric contents.