How It Works
Bottom Line: Chapparal cannot treat or cure cancer or any other medical condition.
Chaparral is derived from the leaves and twigs of the creosate bush, a native American herb that has been used for inflammation 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, using chaparral is not worth the 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 case reports 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
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.
