Cascara Sagrada (Frangula purshiana): Uses, Evidence and Safety

Safety first: cascara is a stimulant laxative for short-term use only. The EU herbal committee (HMPC) says cascara preparations are for the short-term treatment of occasional constipation, should not be taken for more than one week, and must not be used in pregnancy, while breastfeeding or by children under 12. [1] Long-term use may lead to the bowels not working properly and to dependence on laxatives. [1] In the US, FDA's over-the-counter drug rule lists cascara sagrada ingredients among laxative ingredients for which there are "inadequate data to establish general recognition of the safety and effectiveness." [2] Laxative misuse is also a feature of some eating disorders; see eating disorders, weight-loss supplements and laxative misuse. In the US, call or text 988 in a crisis.

What cascara is

Cascara is the bark of the tree the EU committee names Rhamnus purshiana DC. [1] GBIF's accepted name is Frangula purshiana (DC.) J.G.Cooper, family Rhamnaceae, so the two names refer to the same plant in these sources. [3] It contains anthraquinones, compounds comparable to those in other herbal laxatives such as senna. [1] See the senna profile and herbs for constipation.

Traditional use

Proper evidence not found: the sources we read do not describe the traditional use of cascara by a named people or region, so we do not describe it. The EU committee's conclusion rests on "well-established use" in occasional constipation, meaning bibliographic data on effectiveness and safety covering at least 10 years in the EU. [1]

What research and official bodies say

Forms

The EU committee's conclusions cover dried, cut bark and liquid or dry extracts made with water or ethanol, standardized to a defined anthraquinone amount; products are usually herbal tea or solid and liquid forms. [1] Tea, tablet and extract are not interchangeable. See senna and other laxative teas. We give no amounts for a reader.

Safety

• Duration and dependence: the EU monograph says long-term use of stimulant laxatives should be avoided, and cascara should be used only if diet change or bulk-forming agents fail. [5]
• Side effects: allergic reactions, belly pain and spasm, diarrhea, darkened bowel lining that usually recovers after stopping, water and salt imbalance, and protein or blood in the urine with long use. [1][5]
• Potassium and medicines: use with diuretics, corticosteroids and licorice root may increase potassium loss; people taking heart glycosides, antiarrhythmics or QT-prolonging medicines must consult a doctor. [5] See how interactions work.
• Pregnancy and breastfeeding: contraindicated, citing experimental data on genotoxic risk of related compounds and small amounts of an active metabolite found in breast milk. [5] See pregnancy and breastfeeding.
• Children: under 12, not to be used. [1]
• Liver: the monograph says chronic overdoses of anthranoid-containing medicines may lead to toxic hepatitis. [5]
• Kidney: people with kidney disorders should be aware of possible electrolyte imbalance. [5]
• Eating disorders: the NHS lists taking laxatives among purging behaviors in bulimia and warns of physical problems from overusing them. [6]
• Surgery, allergy: hypersensitivity is a listed contraindication. [5] Surgery is not described in the sources we read; tell the surgical team (guide).