Senna can not drink overnight. Senna is brown with a special aroma and taste slightly sweet Chinese medicine, generally drink tea warm drink better, overnight cold and easy to breed bacteria cause or aggravate gastrointestinal symptoms. 1. The role of heat diarrhea, laxative used for defecation disorders, colonoscopy and surgical treatment. 2. Side effects include abdominal pain, diarrhea, fatigue and dizziness, etc.; elderly and infirm, children, menstruation, diabetic patients and severe liver and kidney insufficiency should be used with caution; pregnancy and childbirth, allergy and diarrhea is prohibited; during the use of food should not eat cold, greasy, spicy and stimulating food, and should not be used in conjunction with other laxative drugs. If you feel unwell, it is recommended to go to the gastroenterology department of regular hospitals for consultation and treatment. The efficacy of single medicine is limited, please take it under the guidance of a doctor, and do not blindly take it on your own in order to avoid delaying your condition.