Rhamnus purshiana, a member of the buckthorn family was called Cascara Sagrada ("Sacred Bark") by the early Spanish explorers. The bark of this shrub or small tree contains nearly 10% anthraglycosides as its active ingredient.
It is sold by itself or in combination with other ingredients in laxative, cleansing, and detoxification products.
Do not use Cascara Sagrada during pregnancy, as it may stimulate uterine contractions.
Parke-Davis recognized its use as an herbal laxative, and marketed it as such as early as 1877. It is still one of the best herbal laxatives available today (along with Cape Aloes and Senna), because it is both quick and mild.
The US FDA in February of 2002 issued a final ruling that aloe and Cascara sagrada will not be included in the final monograph for over-the-counter (OTC) laxative drug products because they have not been shown to be generally safe and effective as stimulant laxatives. According to the ruling, aloe extract, aloe flower extract, cascara fluid extract aromatic, Cascara sagrada extract, casanthranol, Cascara sagrada bark and Cascara sagrada fluid extract will no longer be allowed in OTC laxative drug products and are not GRAS (Generally Recognized As Safe).
Cascara Sagrada bark is "Approved" by the German Commission E for constipation.