Other Name(s):

Aulne Noir, Bitter Bark, Bois Noir, Bois à Poudre, Borzène, Bourgène, Buckthorn, California Buckthorn, Cáscara, Cascara Sagrada, Chittem Bark, Dogwood Bark, Écorce Sacrée, Frangula purshiana, Nerprun, Pastel Bourd, Purshiana Bark, Rhamni Purshianae Cortex, Rhamnus purshiana, Rhubarbe des Paysans, Sacred Bark, Sagrada Bark, Yellow Bark.


Cascara is a shrub. The dried bark is used to make medicine.

Cascara used to be approved by the federal Food and Drug Administration (FDA) as an over-the-counter (OTC) drug for constipation. However, over the years, concerns were raised about cascara's safety and effectiveness. The FDA gave manufacturers the chance to submit safety and effectiveness information to answer these concerns. But the companies decided the cost of conducting safety and effectiveness studies would likely be more than the profit they could expect from sales of cascara. So they didn't comply with the request. As a result, the FDA notified manufacturers to remove or reformulate all OTC laxative products containing cascara from the U.S. market by November 5, 2002. Today, you can buy cascara as a “dietary supplement,” but not as a drug. “Dietary supplements” don't have to meet the standards that the FDA applies to OTC or prescription drugs.

Cascara is used as a laxative for constipation, as well as a treatment for gallstones, liver ailments, and cancer. Some people use it as a “bitter tonic.”

In foods and beverages, a bitterless extract of cascara is sometimes used as a flavoring agent.

In manufacturing, cascara is used in the processing of some sunscreens.

How does it work?

Cascara contains chemicals that stimulate the bowel and have a laxative effect.


Pancreatitis is inflammation of an organ in the abdomen called the pancreas. See Answer

Uses & Effectiveness

Possibly Effective for...

  • Constipation. Cascara has laxative effects and may help relieve constipation in some people.

Possibly Ineffective for...

Insufficient Evidence to Rate Effectiveness for...

  • Gallstones.
  • Liver disease.
  • Cancer.
  • Other conditions.
More evidence is needed to rate the effectiveness of cascara for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Side Effects

Cascara is POSSIBLY SAFE for most adults when taken by mouth for less than one week. Side effects include stomach discomfort and cramps.

Cascara is POSSIBLY UNSAFE when used long-term. Don't use cascara for longer than one or two weeks. Long-term use can cause more serious side effects including dehydration; low levels of potassium, sodium, chloride, and other “electrolytes” in the blood; heart problems; muscle weakness; and others.


Super Tips to Boost Digestive Health: Bloating, Constipation, and More See Slideshow

Special Precautions & Warnings

Pregnancy and breast-feeding: Not enough is known about the use of cascara during pregnancy. Stay on the safe side and avoid use if you are pregnant. Cascara is POSSIBLY UNSAFE when taken by mouth while breast-feeding. Cascara can cross into breast milk and might cause diarrhea in a nursing infant.

Children: Cascara is POSSIBLY UNSAFE in children when taken by mouth. Don't give cascara to children. They are more likely than adults to become dehydrated and also harmed by the loss of electrolytes, especially potassium.

Gastrointestinal (GI) disorders such as intestinal obstruction, Crohn's disease, ulcerative colitis, appendicitis, stomach ulcers, or unexplained stomach pain: People with any of these conditions should not use cascara.


Digoxin (Lanoxin)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cascara is a type of laxative called a stimulant laxative. Stimulant laxatives can decrease potassium levels in the body. Low potassium levels can increase the risk of side effects of digoxin (Lanoxin).

Medications for inflammation (Corticosteroids)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications for inflammation can decrease potassium in the body. Cascara is a type of laxative that might also decrease potassium in the body. Taking cascara along with some medications for inflammation might decrease potassium in the body too much.

Some medications for inflammation include dexamethasone (Decadron), hydrocortisone (Cortef), methylprednisolone (Medrol), prednisone (Deltasone), and others.

Medications taken by mouth (Oral drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cascara is a laxative. Laxatives can decrease how much medicine your body absorbs. Decreasing how much medicine your body absorbs can decrease the effectiveness of your medication.

Stimulant laxativesInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cascara is a type of laxative called a stimulant laxative. Stimulant laxatives speed up the bowels. Taking cascara along with other stimulant laxatives could speed up the bowels too much and cause dehydration and low minerals in the body.

Some stimulant laxatives include bisacodyl (Correctol, Dulcolax), castor oil (Purge), senna (Senokot), and others.

Warfarin (Coumadin)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cascara can work as a laxative. In some people cascara can cause diarrhea. Diarrhea can increase the effects of warfarin and increase the risk of bleeding. If you take warfarin, do not take excessive amounts of cascara.

Water pills (Diuretic drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Cascara is a laxative. Some laxatives can decrease potassium in the body. "Water pills" can also decrease potassium in the body. Taking cascara along with "water pills" might decrease potassium in the body too much.

Some "water pills" that can decrease potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDiuril, Microzide), and others.


The following doses have been studied in scientific research:


  • As a laxative for constipation: 20-30 mg per day of the active ingredient (hydroxyanthracene derivatives). A typical dose is 1 cup of tea, which is made by steeping 2 grams of finely chopped bark in 150 mL of boiling water for 5-10 minutes, and then straining. The cascara liquid extract is taken in a dose of 2-5 mL three times daily. The appropriate amount of cascara is the smallest dose that is needed to maintain soft stools.

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