There is no doubt that Cascara has long been relied upon as a treatment for chronic and occasional constipation. It has since become one of the most important herbs used by herbalists to treat constipation. Unlike other laxatives like Senna (Cassia angustifolia), Cascara is said to restore tone to the entire intestinal tract, probably through the activity of its bitter principles and tannins. Although aging or heating the bark appears to decrease its spasmogenic properties, most herbalists will tend to combine Cascara with antispasmodic herbs such as Zingiber to prevent any adverse effects. It is also known that with similar herbs, such as the Chinese Rheum palmatum, that boiling the bark or wood for at least an hour and a half can reduce the purgative property upwards of 50%. This latter technique is especially important if the intent is to take advantage of Cascara’s antitumor properties, without the need to necessarily stimulate bowel movements.