3rd edition, revised Jan 2006
The role of your cancer health professional is to create an environment of openness and trust, and to help in making informed decisions about alternative/ complementary therapies. Collaboration will improve the safe integration of all therapies during your experience with cancer. The "Summary" and "Professional Evaluation/ Critique" sections of this Unconventional Therapies manual are cited directly from the medical literature, and are intended to help in the objective evaluation of alternative/complementary therapies.
Summary
December 21, 2005 Health Canada is warning consumers not to ingest the herb chaparral in the form of loose leaves, teas, capsules or bulk herbal products because of the risk of liver and kidney problems.
"Consumers should stop ingesting retail products containing chaparral and seek medical attention if they have experienced symptoms such as nausea, vomiting, abdominal cramps, fever, fatigue or jaundice (e.g. dark urine, yellow discolouration of the eyes). To date, Health Canada has received one report of acute hepatitis associated with chaparral ingestion." http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/2005/2005_135_e.html
"The chemistry of chaparral is well studied and extensive literature has been published on the principal lignan component, NDGA [nordihydroguaiaretic acid]. However, little documented evidence is available to justify the herbal uses of chaparral. In view of the concerns over the hepatic toxicity, the use of chaparral as a herbal remedy cannot be recommended." (Newall)
"Although the pathophysiology of chaparral-induced hepatotoxicity remains unknown and attribution of adverse health events is complex, the growing number of reports of serious adverse events raises serious questions about the safety of chaparral." (Nasreen)
Description/ Source/ Components
Chaparral is prepared by grinding leaves and twigs of an evergreen desert shrub known as the Creosote Bush called Larrea divericata Coville or Larrea tridentata Coville. (Ontario) (Gordon)
"The active ingredient of chaparral is a potent antioxidant, nordihydroguaiaretic acid (NDGA)." (Gordon)
History
Chaparral tea is an old Indian remedy for cancer. Researched by the University of Utah, it is marketed by Jason Winters as part of an herbal remedy which allegedly cures cancer. (Wilson)
Proponent/ Advocate Claims
"An aqueous extract of the leaves and twigs, so-called chapparal tea, is an old Indian remedy and has been used for a wide variety of ailments, including arthritis, cancer, venereal disease, tuberculosis, bowel cramps, rheumatism, and colds. It is said to possess analgesic, expectorant, emetic, diuretic, and anti-inflammatory properties." (Tylor)
An in vitro study shows that esculetin and NDGA together can suppress cell growth. (Earashi)
"Dried chaparral is described as one of the best herbal antibiotics, being useful against bacteria, viruses and parasites, both internally and externally." (Smith)
An 85-year-old male with a proven malignant melanoma of the right cheek with a larger cervical metastasis (cancer transferred to the neck), refused surgery and treated himself with chaparral tea. He returned eight months later with marked regression of the cancer. According to information received from a physician at the University of Utah, four patients have responded to some extent to treatment with the tea, including two with melanoma, one with choriocarcinoma metastatic to the lungs and one with widespread lymphosarcoma. (CA)
Dr. Hugh H. Hogle, a resident in surgery at the University of Utah presented a paper discussing the use of chaparral tea in the treatment of cancer at a meeting of the Utah Chapter of the American College of Surgeons. This was reported by the lay press, resulting in national and international publicity. (Smart)
Professional Evaluation/ Critique
"Despite studies showing that NDGA to have an anticancer effect in vitro [in an artificial environment], earlier research by the National Cancer Institute found no such effect in vivo [in a living body]. Some reports suggest that NDGA may stimulate certain malignancies such as renal cell carcinoma." (Fetrow)
"Chaparral may also be mutagenic. One case has been described where a patient developed cystic renal cell carcinoma after regularly drinking chaparral tea." (Ernst)
In a case report, a 56-year-old woman was diagnosed as having numerous microscopic and macroscopic cysts in the kidney. "The patient admitted to consuming 3 to 4 cups daily of chaparral tea in a 3-months period approximately 1 1/2 years before surgery." (Smith)
"NDGA [nordihydroguaiaretic acid] is a versatile molecule which has an antitumour capacity probably related with the inhibition of the lipoxygenase activity... It is known that the chemical inhibits cellular division in vitro... however the mitotic decrease was not present in the in vivo study, probably because of the action of an efficient detoxification system." (Madrigal-Bujaidar)
"Because NDGA (nordihydroguaiaretic acid) possesses considerable toxicity; long-term feeding studies in rats induced lesions in the mesenteric lymph nodes and kidneys. As a result, the compound was removed from the FDA's [U.S. Food and Drug Administration's] 'generally recognized as safe' (GRAS) list in 1968." (Tyler)
"Chapparal is considered to be an unsafe herb and was removed by the FDA from its `generally recognized as safe' list in 1970." (Fetrow)
Toxicity/ Risks
"Chapparal tea can cause severe liver toxicity with cholestasis and hepatocellular injury, which resolved with discontinuation and recurred with challenge in one reported case leading to fulminant hepatic failure requiring a liver transplant. There is also the possibility of renal disease resulting from chronic chaparral tea ingestion." (Spencer)
Large amounts may cause nausea, loss of appetite, gastric pain and vomiting. (Ontario)
"A 60-year-old woman took chaparral for 10 months and developed severe hepatitis for which no other cause could be found." The un-ingested chaparral capsules of the 60-year-old woman were not analyzed for impurities which means "it is conceivable that some component other than NDGA may have been the injurious agent." Patients of three other reported cases also ingested chaparral capsules for several months and developed chaparral hepatotoxicity which had significant increase in transaminases and jaundice. (Gordon)
"Excessive doses may interfere with monoamine oxidase inhibitor (MAOI) therapy, because of the documented amino acid constituents."(Newall)
Costs
The cost is approximately $13 for a 50mL bottle. (Ontario)
References
CA (Anonymous). Unproven methods of cancer treatment: chaparral tea. CA: a Cancer Journal for Clinicians 1970;20:112-113.
Ernst E. Complementary medicine, an objective appraisal. Oxford: Butterworth Heinemann, 1996:114-115.
Earashi M, et al. Effects of eicosanoid synthesis inhibitors on the in vitro growth and prostaglandin E and leukotriene B secretion of a human breast cancer cell line. Oncology 1995 Mar-Apr;52(2):150-155.
Fetrow CW, Avila JR. Professional's handbook of complementary and alternative medicines. Springhouse, Pennsylvania: Springhouse Corporation 1999:154-55.
Gordon DW, et al. Chaparral ingestion: the broadening spectrum of liver injury caused by herbal medications. JAMA 1995 Feb 8;273(6):489-490.
Health Canada. Warning: Health Canada warns consumers not to take products containing chaparral. December 21, 2005. http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/2005/2005_135_e.html Accessed January 9, 2006.
Nasreen M, et al. Chaparral-associated hepatotoxicity. Arch Intern Med 1997;157:913-919.
Newall CA, et al. Herbal medicines, a guide for health-care professionals. London: Pharmaceutical press, 1996:74-75.
Ontario Breast Cancer Information Exchange Project. Guide to unconventional cancer therapies. 1st ed. Toronto: Ontario Breast Cancer Information Exchange Project, 1994:54-56.
Smart CR, et al. An interesting observation on nordihydroguaiaretic acid (NSC-4291; NGDA) and a patient with malignant melanoma: a preliminary report. Cancer Chemother Rep 1969 part 1;53:147-151.
Smith AY, et al. Cystic renal cell carcinoma and acquired renal cystic disease associated with consumption of chaparral tea: a case report. Journal of Urology 1994 Dec;152:2089-2091.
Spencer JW, Jacobs JJ. Complementary/ alternative medicine: an evidence based approach. Toronto: Mosby, 1999:147-8.
Tyler VE, Foster S. Tyler's honest herbal: a sensible guide to the use of herbs and related remedies 4th Ed. New York: Haworth Herbal Press, 1999:109-111.
Wilson BR (M.D.). Cancer quackery primer. Dallas, Oregon: The author, 1986.
Revised February 2000