Botanical name(s):

Rhamnus purshiana. Family: Rhamnaceae

Other name(s):

bitter bark, sacred bark

General description

Cascara sagrada was first used by Native Americans. It means “sacred bark”. It’s made from the bark of a tree found in the northwestern U.S.

The bark contains anthraquinone glycosides. This acts as a cathartic or laxative. Cascara may help relieve constipation. But in 2002, the FDA marked laxatives that contain cascara sagrada as category II agents. This means they are not generally recognized as safe and effective for over-the-counter use. Manufacturers had not done the studies to show the safety of cascara sagrada. 

Medically valid uses

Cascara is used to treat constipation. The usual dose is 300 mg 1 time a day. Taking cascara at a higher dose or for longer than 6 days is not advised. .

When taken by mouth, it has these effects:

• Acts as a laxative or purgative and bowel movements

• Empties the colon

Unsubstantiated claims

There may be benefits that have not yet been proven through research.

Cascara may help treat parasitic infestations.

Dosing format

Cascara sagrada comes as oral tablets, capsules, and syrup. Follow the instructions on the package for the correct dose. Cascara is also prepared as a tea or aromatic fluid extract. The aromatic fluid extract dosage is 1 ml.

Side effects, toxicity, and interactions

Side effects include stomach cramping and diarrhea.

As with any laxative, you should not it use when you have stomach pain, nausea, or vomiting. Do not use cascara if you have chronic intestinal problems. These include Crohn's disease, ulcerative colitis, sprue, or irritable bowel syndrome.

Women who are pregnant or breastfeeding should not use cascara sagrada.

Don't take a higher than recommended dose. There are reports of liver toxicity when taken long term in higher than recommended doses or for more than 6 days in a row.

The bark is considered safe only after it’s been aged for 1 year.