Cascara sagrada (Frangula purshiana) is a shrub. The dried bark used to be FDA approved as an OTC laxative for constipation. It’s now used in supplements.

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

People use cascara sagrada for constipation, emptying the colon before a colonoscopy, and other conditions, but there is no good scientific evidence to support these uses.

Cascara sagrada used to be approved by the US FDA as an over-the-counter (OTC) drug for constipation, but this approval was taken away in 2002 due to a lack of evidence. Today, you can buy cascara sagrada as a dietary supplement, but not as a drug

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for CASCARA SAGRADA are as follows:

Possibly ineffective for…

• Emptying the colon before a colonoscopy. Taking cascara sagrada by mouth, along with magnesium sulfate or milk of magnesia, does not improve bowel cleansing in people who are having a colonoscopy.

There is interest in using cascara sagrada for a number of other purposes, but there isn’t enough reliable information to say whether it might be helpful.

When taken by mouth: Cascara sagrada is possibly safe when used for less than one week. Side effects include stomach discomfort and cramps. But cascara sagrada is possibly unsafe when used for more than one week. This could cause more serious side effects, including dehydration, low levels of electrolytes, heart problems, muscle weakness, and others.

Special precautions & warnings:

Pregnancy: There isn’t enough reliable information to know if cascara sagrada is safe to use when pregnant. Stay on the safe side and avoid use.

Breast-feeding: Cascara sagrada is possibly unsafe when taken by mouth while breast-feeding. Cascara sagrada can cross into breast milk and might cause diarrhea in a nursing infant.

Children: Cascara sagrada is possibly unsafe when taken by mouth in children. Don’t give cascara sagrada to children. They are more likely than adults to have serious side effects, including dehydration and low potassium levels.

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

Moderate

Be cautious with this combination.

Digoxin (Lanoxin)

Cascara sagrada 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 from digoxin.

Medications for inflammation (Corticosteroids)

Cascara sagrada is a type of laxative called a stimulant laxative. Stimulant laxatives can cause diarrhea and decrease potassium levels. Some medications for inflammation, called corticosteroids, can also decrease potassium levels. Taking these products together might cause potassium levels to drop too low.

Stimulant laxatives

Cascara sagrada is a type of laxative called a stimulant laxative. Stimulant laxatives can cause diarrhea and decrease potassium levels. Taking cascara sagrada with other stimulant laxatives might cause more diarrhea and very low potassium levels.

Warfarin (Coumadin)

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

Water pills (Diuretic drugs)

Cascara sagrada is a laxative. Some laxatives can cause diarrhea and decrease potassium levels. “Water pills” can also decrease potassium levels. Taking cascara sagrada along with “water pills” might make potassium levels drop too low.

Chromium-containing herbs and supplements

Cascara sagrada contains chromium. Taking it with other supplements that contain chromium can increase the risk of chromium poisoning. Examples of supplements that contain chromium include bilberry, brewer’s yeast, and horsetail.

Herbs that contain cardiac glycosides

Cascara sagrada contains chemicals that can affect the heart. These chemicals are called cardiac glycosides. Using it along with other supplements that also contain cardiac glycosides can increase the risk of heart damage. Examples of supplements that contain cardiac glycosides include black hellebore, foxglove, lily-of-the-valley, oleander, and pleurisy root.

Horsetail

Horsetail can act as a “water pill.” “Water pills” can decrease potassium levels. Cascara sagrada is a laxative. Laxatives can also decrease potassium levels. Taking cascara sagrada along with horsetail might make potassium levels drop too low.

Licorice

Licorice causes the body to lose potassium. Cascara sagrada is a laxative. Laxatives can also decrease potassium levels. Taking cascara sagrada along with licorice might make potassium levels drop too low

Stimulant laxative herbs

Cascara sagrada s a type of laxative called a stimulant laxative. Stimulant laxatives can cause diarrhea and decrease potassium levels. Taking cascara sagrada with other supplements with similar effects might cause more diarrhea and very low potassium levels. Examples of supplements with this effect include aloe, alder buckthorn, gossypol, rhubarb, and senna.

There are no known interactions with foods.

Cascara sagrada used to be approved by the US FDA as an over-the-counter (OTC) drug for constipation, but this approval was taken away in 2002 due to a lack of evidence. Today, you can buy cascara sagrada as a dietary supplement, but not as a drug.

There isn’t enough reliable information to know what an appropriate dose of cascara sagrada might be. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult a healthcare professional before using.

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.

To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.

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