Cascara sagrada (Frangula purshiana)

Synopsis

Cascara sagrada (Spanish for “sacred bark”) refers to the dried bark of the Rhamnus purshiana tree, a deciduous plant native to the Pacific Northwest of North America. Long used by Indigenous tribes and later adopted into Western herbalism, cascara sagrada is best known for its powerful yet gentle laxative effects, making it a common ingredient in natural bowel regulation formulas. Its effectiveness lies in its content of anthraquinone glycosides, particularly cascarosides, which stimulate peristalsis (intestinal contractions) and support colon motility.

Primary therapeutic uses of cascara sagrada include:

  • Relieving occasional constipation
  • Encouraging regular bowel movements
  • Supporting colon cleansing and detoxification
  • Restoring bowel tone in cases of sluggish digestion or after long-term laxative use
  • Sometimes used in liver and gallbladder support formulas for its mild bile-stimulating effect

Cascara sagrada must be aged for at least a year or heat-treated before use to reduce the risk of harsh effects and nausea. It is commonly found in teas, tinctures, capsules, and herbal laxative blends.

Active compounds include:

  • Anthraquinone glycosides (cascarosides A–D) – stimulate bowel movement
  • Tannins and resins – contribute mild astringency and toning
  • Aloe-emodin – has antimicrobial and mild anti-inflammatory activity

Historical Use:

Cascara sagrada was used traditionally by Native American tribes, such as the Salish and Chinook, for its laxative, digestive, and purgative properties. They prepared it as a decoction for treating constipation and gastrointestinal discomfort.

It was introduced to Western medicine in the late 1800s, quickly becoming a primary botanical laxative in the U.S. Pharmacopeia and a common over-the-counter remedy for constipation through the mid-20th century.

Despite its historical popularity, cascara sagrada has since been reclassified by the FDA (for over-the-counter use) due to insufficient safety data for chronic use. However, it remains widely available as an herbal supplement, often included in short-term bowel-cleansing and detox protocols.

Today, cascara sagrada is valued in natural medicine for its gentle, non-habit-forming support of digestive regularity, especially when used short-term and in combination with soothing herbs like ginger or licorice. It is not recommended for prolonged use, as overuse may lead to electrolyte imbalance or dependency.

Other names

cascara sagrada
sacred bark

Historical and Science-based Use

This ingredient is used to address these health conditions and support these body systems. Note that we list whether the use is historical/traditional or science-based. If science-based, we are including a score from A-F (based on the number of studies done and the quality of those studies).

Conditions

Constipation (adults) (Traditional)
Constipation (children) (Traditional)
Colon (atonic) (Traditional)
Digestion (poor) (Traditional)
Gas and Bloating (Traditional)
Indigestion (Traditional)
Liver Detoxification (Traditional)
Ulcers (Traditional)

Body Systems

Gall Bladder (Traditional)
Large Intestines (Colon) (Traditional)
Digestive System (Traditional)
Gastrointestinal Tract (Traditional)
Intestinal System (Traditional)
Liver (Traditional)
Rectum (Traditional)