Pregnancy diarrhea may be caused by gastrointestinal colds, gastroenteritis, irritable bowel syndrome, etc. It can be treated with medicines such as montelukast and lactobacillin tablets. 1. Gastrointestinal cold: pregnant women may sneeze, headache, abdominal pain, diarrhea and other cold symptoms after catching a cold, you can take cold medicine such as Lianhua Qingdian capsule, for diarrhea, you can take montelukast to stop diarrhea. 2. Gastroenteritis: pregnant women who eat unclean food may cause gastroenteritis, abdominal pain, diarrhea symptoms, then you can take lactobacillus tablets to regulate the gastrointestinal, the use of montelukast for antidiarrheal treatment. 3. Irritable bowel syndrome: pregnant women who previously suffered from irritable bowel syndrome, will also appear abdominal pain, diarrhea symptoms, can use montelukast to stop diarrhea treatment. Pregnant women who have diarrhea during pregnancy are advised to go to the hospital in a timely manner, can use the appropriate medication under the guidance of the doctor, if dehydration occurs, should also be rehydration therapy.