Cascara Sagrada

Fact Sheet

It is from the bark of this tree that the drug, Cascara Sagrada, is obtained.

Julia Rogers/Flickr


Cascara sagrada has a long history of traditional use by native Americans. Cascara sagrada contains compounds called anthraquinones, which are responsible for cascara's powerful laxative effects. Anthraquinones trigger contractions in the colon called peristalsis, which causes the urge to have a bowel movement. 

In addition to being a powerful laxative, cascara is also believed to improve the muscle tone of the colon walls. It is used as an alternative medicine for constipation.

Cascara can be found in various forms: capsules, liquid extracts, and dried bark. The dried bark can be made into tea, although it tastes bitter. Cascara sagrada's alternate names are rhamnus purshiana, cascara, California buckthorn, and sacred bark.

Fresh cascara bark should not be used because it may cause bloody diarrhea and vomiting. Some proponents say that the bark should be aged for at least one year or put through a special heat treatment.


Long-term use of cascara sagrada is not recommended.

Pregnant or nursing women should not use cascara sagrada. Children should not use cascara sagrada.

Cascara or other anthraquinone-containing herbs should not be used by people with diverticular disease, ulcerative colitis, Crohn's disease, severe hemorrhoids, blood vessel disease, congestive heart failure, heart disease, severe anemia, abdominal hernia, gastrointestinal cancer, recent colon surgery, or liver and kidney disease. It should not be used if appendicitis is suspected.

Cascara may interact with drugs called cardiac glycosides, such as digitalis.

Side effects of cascara may include strong cramping in the abdomen (due to muscle contractions, electrolyte imbalance (loss of potassium) and loss of body fluids, and dark pigmentation in the colon, called melanosis coli with longer-term use. Call your doctor if you experience bloody diarrhea, discolored urine, vomiting, or prolonged abdominal pain after using cascara.

There has been one report of the development of cholestatic hepatitis, complicated by portal hypertension, after use of cascara. Long-term use of anthraquinones has been linked to the development of colorectal growths (adenomas) and cancer.

Large doses of anthraquinones may cause bloody diarrhea or vomiting. Long-term use can cause dependence.

Using Cascara

Due to a lack of supporting research, it's too soon to recommend cascara sagrada for any health condition. Supplements haven't been tested for safety and due to the fact that dietary supplements are largely unregulated, the content of some products may differ from what is specified on the product label. Also, keep in mind that the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established. You can get tips on using supplements but if you're considering the use of cascara sagrada, talk with your primary care provider first. Self-treating a condition and avoiding or delaying standard care may have serious consequences.

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Article Sources
  • Feltrow, C.W. and J.R. Avila. The Complete Guide to Herbal Medicines. New York: Simon and Schuster, 2000.
  • Lust, John. The Herb Book: The Complete and Authoritative Guide to More Than 500 Herbs. New York: Benedict Lust Publications, 2005.
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  • Willems M, van Buuren HR, de Krijger R. Anthranoid self-medication causing rapid development of melanosis coli. Neth J Med. 2003 Jan;61(1):22-4.