How It Works
Bottom Line: Chapparal can not treat or cure cancer or any other medical condition. This herb can be dangerous and should be avoided.
Chaparral is derived from the leaves and twigs of the creosate bush, a native American herb that has been used for inflammatory and cancer. It contains biologically active molecules that have been found to block cellular division in laboratory studies. However, when chaparral extracts were tested in living bodies (animal studies), no such effect was found. Because several patients who regularly drank chaparral tea developed kidney cysts, kidney cancer, and liver damage, it is generally accepted that using chaparral is not worth the health risks.
Purported Uses
NOTE: No scientific evidence supports the use of chaparral for any of the following uses, and serious side effects (such as liver and kidney damage) are associated with the use of chaparral.
- To treat arthritis
- To treat bronchitis and the common cold
- To prevent and treat cancer
- To reduce inflammation
- To alleviate menstrual cramps
- To promote urination
- To stop muscle spasms
Research Evidence
One clinical trial found chaparral ineffective as an anticancer agent. In addition, there are several reported cases of liver damage and other adverse effects in patients who ingested chaparral. These include:
- Thirteen cases of liver damage, of which four progressed to cirrhosis and two required liver transplants.
- Two cases of liver toxicity from daily ingestion of chaparral, which improved after chaparral was discontinued.
- One case of severe liver damage requiring a liver transplant after consuming chaparral for ten months.
Warnings
- Chaparral has been associated with severe liver damage, in some cases requiring liver transplantation.
- In 1992, the F.D.A. issued a health warning urging withdrawal of all chaparral products.
Do Not Take If
- You are taking MAOIs (High doses of chaparral may interfere with their effects).
- You have liver or kidney problems.
Side Effects
- Fatigue
- Contact dermatitis
- Stomach upset
- Jaundice (yellowing of the skin)
- Liver damage
- Cirrhosis of the liver
- Acute hepatitis
- Kidney failure
- Renal cell carcinoma
Scientific Name
Larrea tridentate, Larrea divaricata
Common Name
Creosate bush, greasewood, hediondilla
Clinical Summary
Derived from the leaves and flowers of the plant. Chaparral is a native American herb that has purported antiinflammatory and anticancer effects. However, a phase II clinical trial showed chaparral to be ineffective as an anticancer agent
(9). Numerous reports indicate hepatotoxicity following the use of chaparral
(4) (7) (8). Although a small retrospective study indicates that low intake of chaparral tincture (<10%) appears to have no adverse effects
(3), correlation between length of exposure and risk is not yet determined. Nordihydroguaiaretic acid (NDGA), the principal ingredient in chaparral, was removed from the FDA's "Generally Recognized as Safe" (GRAS) list in 1968
(1). Due to case reports involving both reversible and irreversible liver damage, the FDA issued a health warning urging withdrawal of chaparral products in 1992. The use of chaparral as an herbal remedy cannot be recommended.
Purported uses
- Arthritis
- Bronchitis
- Cancer prevention
- Cancer treatment
- Common cold
- Inflammation
- Menstrual cramps
- Promote urination
- Spasms
Constituents
- Amino Acids: Arginine, aspartine, cystine, glutamic acid, glycine, isoleucine, leucine, phenylalanine, tryptophan, tyrosine, valine
- Flavonoids: More than 20 different reported, including isorhamnetin, kaempferol and quercetin and their glycosidic and ether derivatives; gossypetin, herbacetin and their acetate derivatives
- Lignans: Nordihydroguaiaretic acid, norisoguaiacin, dihydroguaiaretic acid
- Resins: A number of flavone and flavonol glycosides
- Volatile Oils: Terpene components include calamene, eudesmol, & limonene
- Others: Two pentacyclic triterpenes and saponins. A cytotoxic naphthoquinone derivative, larreantin, has been isolated from the roots.
(1)
Mechanism of Action
Nordihydroguaiaretic acid (NDGA) a lipoxygenase inhibitor may be responsible for the biological activity of chaparral. It is believed that NDGA may have anticancer activity by blocking cellular respiration in vitro
(2). However, later studies found no effect in vivo
(3).
Warnings
Chaparral has been associated with severe hepatotoxicity, with some cases requiring liver transplantation
(4) (7) (8).
Adverse Reactions
Reported: Fatigue, jaundice, cirrhosis, hepatotoxicity
(4) (5) (7) (8), acute hepatitis, contact dermatitis, kidney failure, and renal cell carcinoma
(1).
Herb-Drug Interactions
MAO Inhibitors: Excessive doses of chaparral may interfere with monoamine oxidase inhibitor therapy due to the documented amino acid constituents
(1).
Lab Interactions
Elevated liver function tests
Elevated kidney function tests
Literature Summary and Critique
Sheikh NM, et al. Chaparral-associated hepatotoxicity. Arch Intern Med 1997;157: 913-9.
Eighteen case reports of adverse events associated with the ingestion of chaparral reported to the FDA between 1992 and 1994 were reviewed. The results showed evidence of hepatotoxicity in 13 cases. Jaundice occurred 3 to 52 weeks after ingestion of chaparral, and the predominant pattern of liver injury was characterized as toxic or drug-induced cholestatic hepatitis. In four patients progression to cirrhosis occurred, and two patients required liver transplants.
Batchelor WB, et al. Chaparral-induced hepatic injury. Am J Gastroenterol 1995;90:831-3.
Two case studies of hepatitis after daily ingestion of chaparral were presented. Both patients remained well after abstinence from chaparral.
Gordon DW, et al. Chaparral ingestion. The broadening spectrum of liver injury caused by herbal medications. JAMA 1995;273:489-90.
Case study of a patient who developed severe hepatitis after consuming chaparral for 10 months and subsequently required a liver transplant.
Heron S, Yarnell E. The safety of low-dose Larrea tridentata (DC) Coville (creosote bush or chaparral): a retrospective clinical study. J Altern Complement Med 2001;7:175-85.
A retrospective review of 35 patients who used chaparral alone or in combination with other herbs either internally or externally over a 22 month period. No patient showed signs of organ damage. Although the results suggest that chaparral appears to be safe in low doses, this study was based solely on retrospective observation. Out of 35 patients, only 4 patients' outcomes could be verified through blood chemistry. More studies must be performed before a clinically safe dose level can be established.
Smart CR, et al. Clinical experience with nordihydroguaiaretic acid -- "Chaparrel tea" in the treatment of cancer. Rocky Mt Med J. 1970 Nov;67(11):39-43.
A phase II clinical trial of an aqueous extract of chaparrel on 59 patients with advanced incurable cancer. 23 patients were also treated with 250 - 3,000 mg /day of the pure compound. Of the 45 patients considered evaluable after adequate trial, four patients had significant tumor regression. 27 patients had subjective improvement while their tumors rapidly progressed objectively. Because of the significant number of cases of tumor stimulation and dearth of tumor regression, chaparrel tea was not found to be an effective anticancer agent.
References
- Newall CA, et al. Herbal Medicines: A Guide for Health-Care Professionals. London: Pharmaceutical Press; 1996.
- Cunningham DC, et al. Proliferative responses of normal human mammary and MCF-7 breast cancer cells to linoleic, CLA and eicosanoid synthesis inhibitors in culture. Anticancer Res 1997;17:197-203.
- Pavani M, et al. Inhibition of tumoral cell respiration and growth by norhidydroguaiaretic acid. Biochem Pharmacol 1994;48:1935-42.
- Sheikh NM, et al. Chaparral-associated hepatotoxicity. Arch Intern Med 1997;157:913-9.
- Tyler V, et al. The Honest Herbal. New York: Pharmaceutical Press; 1993.
- Heron S, Yarnell E. The safety of low-dose Larrea tridentata (DC) Coville (creosote bush or chaparral): a retrospective clinical study. J Altern Complement Med 2001;7:175-85.
- Batchelor WB, et al. Chaparral-induced hepatic injury. Am J Gastroenterol 1995;90:831-3.
- Gordon DW, et al. Chaparral ingestion. The broadening spectrum of liver injury caused by herbal medications. JAMA 1995;273:489-90.
- Smart CR, et al. Clinical experience with nordihydroguaiaretic acid -- "Chaparrel tea" in the treatment of cancer. Rocky Mt Med J. 1970 Nov;67(11):39-43.
- Gordon DW, et al. Chaparral ingestion. The broadening spectrum of liver injury caused by herbal medications. JAMA 1995;273:489-90.
