

Creosate bush, greasewood, hediondilla
Chaparral is a native American herb that has purported anti-inflammatory 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.
MAO Inhibitors: Excessive doses of chaparral may interfere with monoamine oxidase inhibitor therapy due to the documented amino acid constituents (1).
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.
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.
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.
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.