Buckthorn

Botanical name: Rhamnus catharicus

Parts used and where grown: Buckthorn is a tall shrub native to northern Europe. The dried berries and dried bark are used medicinally. The bark is allowed to dry for up to a year before being used, which reduces the potential of buckthorn to cause vomiting.

Buckthorn has been used in connection with the following conditions (refer to the individual health concern for complete information):

Rating Health Concerns
2Stars Constipation
3Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
2Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
1Star An herb is primarily supported by traditional use, or the herb or supplement has little scientific support and/or minimal health benefit.

Historical or traditional use (may or may not be supported by scientific studies): Buckthorn has been used as a cathartic laxative in northern and central Europe, including England, for centuries.1 While its importance declined when the similar shrub Rhamnus purshiana or cascara sagrada was discovered in America,2 buckthorn is still used, particularly in Europe.

Active constituents: Buckthorn bark and berries are high in anthraquinone glycosides. Resins, tannins, and lipids make up the bulk of the bark’s other ingredients. Buckthorn berries also contain flavonoids. Anthraquinone glycosides have a cathartic action, inducing the large intestine to increase its muscular contraction (peristalsis) and increasing water movement from the cells of the colon into the feces, resulting in strong, soft bowel movement.3 It takes six to ten hours for buckthorn to act after taking it by mouth.

How much is usually taken? Only the dried form of buckthorn berries and bark should be used. Capsules providing 20 to 30 mg of anthraquinone glycosides (calculated as glucofrangulin A) per day can be used; however, the smallest amount necessary to maintain regular bowel movements should be used.4 As a tincture, 5 ml once at bedtime is generally taken. Usually buckthorn is taken at bedtime, so it will have time to act and by morning a bowel movement is induced. It is important to drink eight six-ounce glasses of water throughout the day while taking buckthorn, and to consume plenty of fresh fruits and vegetables. Buckthorn should be taken for a maximum of eight to ten days consecutively or else it can lead to dependence on it to have a bowel movement.5 Some people take peppermint tea or capsules with buckthorn to prevent griping, an unpleasant sensation of strong contractions in the colon sometimes induced by buckthorn.

Are there any side effects or interactions? Buckthorn may turn the urine dark yellow or red, but this is harmless. Women who are pregnant or breast-feeding and children under the age of 12 should not use buckthorn without the advice of a physician. Those with an intestinal obstruction, Crohn’s disease or any other acute inflammatory problem in the intestines, diarrhea, appendicitis, or abdominal pain should not use this herb.6 Use or abuse of buckthorn for more than ten days consecutively may cause a loss of electrolytes (especially the mineral potassium) or may weaken the colon. Long-term use can also cause kidney damage.7

Are there any drug interactions? Certain medications may interact with buckthorn. Refer to the drug interactions safety check for a list of those medications.

References:

1. Lust J. The Herb Book. New York: Bantam Books, 1974:138–40.

2. Evans WC. Trease and Evans’ Pharmacognosy, 13th ed. London: Baillière Tindall, 1989:408.

3. Blumenthal M, Busse WR, Goldberg A, et al, eds. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin: American Botanical Council and Boston: Integrative Medicine Communications, 1998:95–8.

4. Blumenthal M, Busse WR, Goldberg A, et al, eds. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin: American Botanical Council and Boston: Integrative Medicine Communications, 1998:95–8.

5. Blumenthal M, Busse WR, Goldberg A, et al, eds. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin: American Botanical Council and Boston: Integrative Medicine Communications, 1998:95–8.

6. European Scientific Cooperative on Phytotherapy (ESCOP). Frangulae cortex, frangula bark. Monographs on the Medicinal Uses of Plant Drugs. Exeter, UK: University of Exeter, Centre for Complementary Health Studies, 1997.

7. European Scientific Cooperative on Phytotherapy (ESCOP). Frangulae cortex, frangula bark. Monographs on the Medicinal Uses of Plant Drugs. Exeter, UK: University of Exeter, Centre for Complementary Health Studies, 1997.