Common name: Cascara
Other names: Sacred bark, chittem bark, California buckthorn, Persian bark, bearberry, bear wood, shittimwood, holy bark, Christ’s thorn
Latin name: Cascara sagrada
Affinities: Digestive system, nervous system
Actions: Bowel tonic, cathartic
Specific indications: Chronic constipation
Diseases: Chronic constipation(2), mucus colitis(3)
Parts used: Bark
Characteristics: Cascara is a small tree, native to the Pacific Northwest and member of the buckhorn or Rhamnaceae family (Wood, 2009). It is usually between 15 and 20 foot in height with thin leaves that are 2 to 6 inches long, and 1 to 3 inches wide. It has small greenish flowers and grows black berries.
History: In the 16th century Spanish explorers, who first visited what is now Northern California, acquired cascara off the native Americans who used it as a laxative (Castleman, 2001). The Spanish recognised cascara as a relative of buckthorn, a strong laxative herb used in Europe, and found it to be milder and gentler. Cascara was popularised by an Eclectic physician called Dr. J. H. Bundy in Detroit and was entered the U.S. Pharmacopoeia in 1890 (Wood, 2009; Castleman, 2001). Dr. Bundy wrote of cascara, ‘It acts upon the sympathetic nervous system… especially upon the solar plexus, stimulating the nutritive and assimilative forces, increasing the digestive processes generally. It acts upon the secretory system in a marvellous manner, especially where the secretions are deficient and perverted, and this seems to be one of its special indications’ (Wood, 2009).
Finley Ellingwood, another Eclectic physician, further described cascara writing it was, ‘especially indicated in torpidity or atonicity…. It is not a cathartic in the common acceptance of the term, but by restoring normal function… bowel movement of a natural character follows’. Ellingwood also wrote one must use small doses of cascara to achieve this tonic effect to cure constipation, while larger doses can in fact weaken the bowel, he described the dose range as ‘two to ten drops in the proper vehicle be given, three, four, or five times daily for many days, even if the constipation does not at first yield, the effects after a few days are usually salutary’. Once proper movements are re-established Ellingwood stated cascara must be decreased down to just one drop per day (Wood, 2009). Cascara was an ingredient in the Hoxsey Cancer Formula, an alternative therapy for cancer in the 1930s to 1950s constructed by an ex-coal miner named Harry Hoxsey (Castleman, 2001).
Current applications: Cascara is a key bowel tonic herb in traditional Western herbalism. Dr. John R. Christopher highly valued cascara and he used it as the lead herb in his intestinal corrective formula, and in his text, The School of Natural Healing, he mentioned that Cascara sagrada has a very beneficial tonic range in the alimentary canal, increasing the secretions of the stomach, liver, pancreas, and lower bowels (Christopher, 1976). Dr. Christopher considered cascara a regenerative medicine, but stressed the bark must be aged for at least 1 year and with ageing up to 6 years its effects become gentler and the tonic effect becomes stronger. Dr Christopher also wrote that cascara produces large, soft and painless evacuations and, after extended usage, the bowels will function naturally and regularly from its tonic effects.
Cascara may be combined with other herbs in a bowel tonic formula (this is an example from Dr. Christopher), such as; barberry, cayenne, ginger, golden seal root, lobelia, red raspberry, turkey rhubarb, fennel. David Hoffman recommends it is applied together with aromatics and carminatives such as licorice (Hoffman, 1988). The primary use of cascara is for treating constipation and at sensible doses, it is not thought to cause laxative dependency.
Science: It is thought it is the anthraquinones in the bark of cascara that are responsible for its cathartic activity (Sipple et al., 1934). The cathartic activity has been confirmed in experiments using rats (Lish et al., 1958). One experiment on humans found significant improvements compared with placebo, although the experiment was placebo controlled, it was not double blinded (Greiner et al., 1957).
Safety: Moderate-high. Cascara, in the correct form, is one of the safest natural laxatives known, but in larger doses will cause griping and further constipation. Pay attention to the defined dose range either here or from a well-qualified health care provider. Avoid use in pregnancy.
Dosage: 1-10 drops per dose between 1-4 times daily (Wood, 2009). Aim to taper down slowly until it is either not needed or just 1 drop a day is required. Dr. Christopher recommended continuing treatment for several months to get long lasting benefits (Christopher, 1976).
Form: The bark should be dried and aged at least one year before the tincture is made (Christopher, 1976).
Research on models
Cathartic activity: In one study using rats, researchers found that cascara stimulated bowel movements, however, activity was not as strong as pharmaceutical alternatives in their experiments (Lish et al., 1958).
Research on humans
Constipation: A study (n = 20, randomised, placebo controlled) evaluated the effects of cascara versus a placebo in constipated patients, they found it was significantly better than the placebo. Cascara treatment gave improvements in frequency and consistency (Greiner et al., 1957).
Castleman, Michael. “The new healing herbs.” Bantam Book, New York (2001): 465-471.
Greiner, Theodore, Irwin Bross, and Harry Gold. “A method for evaluation of laxative habits in human subjects.” Journal of chronic diseases 6.3 (1957): 244-255.
Hoffman, David. Holistic herbal. Element Books, 1988.
Lish, Paul M., and Kendrick W. Dungan. “Peristaltic‐stimulating and fecal‐hydrating properties of dioctyl sodium sulfosuccinate, danthron, and cascara extracts in the mouse and rat.” Journal of Pharmaceutical Sciences 47.5 (1958): 371-375.
Sipple, Horace L., C. G. King, and George D. Beal. “A study of the constituents in cascara sagrada extract I. Isolation of a rhamno‐glycoside of emodin.” Journal of Pharmaceutical Sciences 23.3 (1934): 205-208.
Wood, Matthew. The Earthwise Herbal: A Complete Guide to New World Medicinal Plants. North Atlantic Books, 2009.