Senna drink a few hours to see the effect can not be generalized, the symptomatic drug case is usually about 2 ~ 12 hours to see the effect. Senna drink a few hours to see the effect, there is no fixed time, it should be based on the treatment of disease, the severity of the disease, clinical experience to comprehensive judgment, such as the use of evidence, generally 2 ~ 12 hours or so to see the effect. Senna is a traditional Chinese medicine, for the bean mountain lentil plant Senna dry leaflets, this traditional Chinese medicine has diarrhea heat stagnation, laxative, diuretic effect. Used for the treatment of heat stagnation, constipation and abdominal pain, edema and fullness. Excessive use of senna leaves may cause abdominal pain, nausea and vomiting. It is contraindicated in weak body, pregnant women, menstruation and lactation. If you need to use the drug, should be by a traditional Chinese medicine practitioner under the guidance of the identification of medication, not to buy their own use of medicines, so as to avoid the delay of the drug is not the right evidence.