The Health Benefits of Cascara Sagrada

This once-popular natural laxative poses certain risks

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

Julia Rogers/Flickr

 

Cascara sagrada (Rhamnus purshiana) is a shrub native to western North America whose bark is processed for medicinal purposes. Used for centuries by native Americans, cascara sagrada contains compounds called anthraquinones that have powerful laxative effects. In addition, cascara sagrada is believed to improve the muscle tone of the colon itself.

Cascara sagrada has been listed on the U.S. Pharmacopeia since the 1890s and received initial approval from the U.S. Food and Drug Administration (FDA) for use as an over-the-counter laxative. However, that approval was rescinded in November 2002 due to concerns about the long-term safety of cascara sagrada and the lack of efficacy research.

Although the FDA gave manufacturers the opportunity to submit research, they declined due to the high cost of clinical trials and instead opted to have their products reclassified as a "dietary supplements" rather than over-the-counter laxatives.

Cascara sagrada should not be confused with cascara—the dried skin of coffee cherries that some use to make lattes and other coffee drinks.

Cascara sagrada is also known by the names California buckthorn, bearberry, yellow bark, and sacred bark, as well as chittem and chitticum in the Chinook jargon of the Pacific Northwest.

Health Benefits

Cascara sagrada is primarily used to treat constipation. The anthraquinones contained in the bark inhibit the absorption of water and electrolytes in the intestines. Because of this, stool volume increases as it absorbs the excess water, which increases pressure within the intestine. This stimulates muscle contractions in the colon (peristalsis), speeding the clearance of the bowel.

As such, cascara sagrada is considered a stimulant laxative alongside other natural laxatives like aloe vera and senna. Unlike these counterparts, the effect of cascara sagrada tends to be gentler, resulting in fewer loose or watery stools. Cascara sagrada also works differently the demulcent laxatives like psyllium, which creates a gel-like substance that helps ease stool from the bowels.

Even though it is no longer an FDA-approved laxative, cascara sagrada is still used by people who prefer "natural" laxatives to chemical ones. It may even be used to prep the bowel prior to a colonoscopy, although its effect is less consistent than Dulcolax (bisacodyl) or magnesium citrate.

Generally speaking, cascara sagrada will induce a bowel movement within six to eight hours of taking a dose.

While cascara sagrada is believed by some to prevent or treat gallstones, liver problems, hemorrhoids, fissures, and even cancer, there is little to no evidence to support these claims.

Possible Side Effects

Cascara sagrada is intended for short-term use only. If used to treat occasional constipation, it is generally safe and well-tolerated. In some cases, it may cause abdominal pain and cramping (most commonly when used to treat severe constipation).

The long-term use of cascara sagrada is another matter and one that has raised concerns among FDA officials. The concerns stemmed primarily the evidence that anthraquinones in cascara sagrada, aloe vera, and senna may be harmful if overconsumed. Cascara sagrada can also cause a condition known as melanosis coli, a discoloration of the lining of the colon.

If taken for more than a week or two, cascara sagrada may cause severe dehydration and the rapid loss of electrolytes such as sodium, potassium, and chloride. This can trigger an array of potentially serious side effects, including:

  • Severe nausea
  • Loss of energy
  • Headaches
  • Muscle weakness, spasms, or cramps
  • Irregular heartbeat (arrhythmia)
  • Skipped heartbeats (palpitations)
  • Rapid heartbeat (tachycardia)
  • Numbness or tingling of the hands or feet (neuropathy)
  • Reduced urine output
  • Confusion
  • Depression
  • Return of constipation (rebound constipation)

Excessive doses of cascara sagrada can cause bloody diarrhea, vomiting, and the inability to urinate (acute urinary retention). Call your doctor or seek urgent care if you experience any of these symptoms.

If used regularly, cascara sagrada can lead to laxative dependence as the intestines begin to adapt to the anthraquinones and become less able to work on their own. The long-term use of anthraquinones has also been linked, albeit weakly, to the development of colorectal growths (adenomas).

Contraindications

Cascara sagrada should never be used for weight loss due to the high risk of side effects and complications.

It should also be avoided in people with diverticular disease, ulcerative colitis, Crohn's disease, severe hemorrhoids, congestive heart failure, cardiovascular disease, severe anemia, abdominal hernia, gastrointestinal cancer, recent colon surgery, liver disease, kidney disease, or suspected appendicitis.

Due to the lack of safety research, cascara sagrada should never be used by children, pregnant women, or nursing mothers.

Drug Interactions

Cascara sagrada may interact with a class of drugs called cardiac glycosides used to treat heart failure, including digoxin, digitoxin, and digitonin. It does so by depleting the body of the sodium and potassium it needs to stimulate heart contractions.

Cascara sagrada may also reduce the efficacy of corticosteroids used to treat inflammation. These drugs work by decreasing potassium in the body, and taking cascara sagrada with one can further this effect, leading to severe hypokalemia.

Advise your doctor if you take cascara sagrada or any other natural laxative to avoid potentially serious interactions or side effects.

Dosage and Preparation

The processing of cascara sagrada bark can differ. It is typically removed, diced, and dried for up to one year to reduce its potency. Some manufacturers will heat the bark to speed the process. The dried bark can then be powdered or boiled and distilled for herbal products.

There is no recommended dosage of cascara sagrada, the effects of which can differ depending on a person's age, weight, health, and co-existing medical conditions.

Further complicating this is the fact that the herb comes in a multitude of formulations, including capsules, powders, tinctures, and teas, which can make it difficult to know how much or little of a product you need to achieve the desired effect.

If you decide to use cascara sagrada, never exceed the dosage listed on the product label or use for more than three days.

What to Look For

Herbal supplements like cascara sagrada do not need to undergo the rigorous testing in the United States that pharmaceutical drugs do. Because of this, the quality of the supplement can vary considerably, particularly if you buy it in its natural "wild-crafted" form.

To ensure quality and safety, only buy supplements that have certified by an independent body such as the U.S. Pharmacopeia (USP), NSF International, or ConsumerLab.

These agencies are tasked with determining the quality of a product and whether it contains the quantity of ingredients listed on its label.

The loose tea usually looks like bark shavings or chips. Avoid teas sold in larger chunks, as they tend to be higher in anthraquinones and may have stronger laxative effects. If buying tea bags, be sure to buy cascara sagrada tea and not cascara tea made from the skins of coffee berries.

Other Questions

Is it safe to use of fresh cascara bark?

Fresh cascara bark should never be used because the anthraquinone content will be far too high and will likely cause severe cramping, vomiting, and bloody diarrhea. Aging of the bark is needed to temper the laxative effect.

How do you make cascara sagrada tea?

To brew the loose tea, steep 2 grams (1 teaspoon) of bark shavings in two-thirds of a cup of boiling water for five to 10 minutes. Strain before drinking.

Cascara sagrada tea has a bitter and slightly resiny taste. Some people like to mix it with black tea, green tea, or rooibos tea for a more palatable flavor.

Was this page helpful?

Article Sources