BACKGROUND Korean cactus Cheonnyuncho (Opuntia humifusa) is rich in pectin, phenols, flavonoids, and minerals such as calcium and phosphorus. Some Koreans drink Cheonnyuncho juice prepared by grinding Cheonnyuncho with water. Cheonnyuncho is well known for its functional properties and antioxidant effects, but its effect on constipation has not been sufficiently studied. METHODS Loperamide (2...