Cascara Sagrada, Rhamnus Purshiana. The U. S. P. directs that the bark be collected at least one year before being used.

Anthraquinone derivatives are present, but no active principle has been isolated. Anthraquinone is closely identified with phenolphthalein.

Cascara is the most generally useful laxative of the whole botanic class, especially in chronic constipation. Fl. 10 to 60 minims. Various flavored or aromatized products are available.