(Nature's Way) Senna is the fast way to help stimulate your lower digestive tract to getting back to regularity. It usually works in 6 to 12 hours to cleanse your system naturally. Recommended daily oral dosage for adults and children over 12 years of age is 2 to 4 capsules once or twice daily with a full 8-ounce glass of water, juice or other liquid. Do not take for more than 1 week as frequent or prolonged use may result in dependence. Senna should be avoided during pregnancy and by nursing mothers. The smallest dose possible should be used to achieve a bowel movement because higher doses can cause abdominal pain, severe cramping, colic and nausea.