Pau d'arco (Tabebuia avellanedae) is native to South America, where it has been used to treat a wide range of conditions, including pain, arthritis, inflammation of the prostate gland (prostatitis), fever, dysentery, boils and ulcers, and various cancers. As early as 1873, there are reports of medicinal uses of Pau d'arco.
Scientists have identified two active chemicals in pau d'arco. These chemicals are called naphthoquinones: lapachol and beta-lapachone. In lab tests, these chemicals kill some bacteria, fungi, viruses, and parasites. They also have anti-inflammatory properties. But no one knows whether they will have the same effects when humans take them, and the usual dose required would have severe, toxic side effects.
Pau d'arco is sometimes used for the following conditions, although there is no evidence it works:
Candidiasis (a vaginal or oral yeast infection)
Herpes simplex virus
Parasitic diseases, such as schistosomiasis
Bacterial infections, such as brucellosis
Test tube and animal studies have looked at whether pau d'arco has any effect on cancer. These tests have shown mixed results. Even in studies where pau d'arco does reduce the number of cancer cells, the amounts used would be toxic to humans.
The same is true of some of the doses that might be needed to kill bacteria or viruses. For this reason, you should take pau d'arco only under your health care provider's supervision.
The pau d'arco tree is an evergreen tree that grows in the warm parts of Central and South America. It is a broad leaf evergreen that grows to a height of 125 feet and has pink-to-violet colored flowers. The tree's extremely hard wood makes it resistant to disease and decay. The inner bark of the tree is used medicinally. In recent years there has been an increasing demand for pau d'arco, causing the trees to be endangered.
What's It Made Of?
Most of the chemical research on pau d'arco has been done on the wood and not the inner bark. Pau d'arco contains chemical compounds called naphthoquinones, specifically lapachol and beta-lapachone. They seem to have antifungal, antiviral, and antibacterial properties. They also contain significant amounts of the antioxidant quercetin.
Pau d'arco is sold as tablets, dried bark tea, and tincture (which contains alcohol). The chemicals that give pau d'arco its medicinal effects don't dissolve well in water, so a tea is not recommended.
Most pau d'arco products are not standardized, so it is hard to determine whether or not they contain a safe amount of these active substances. It is important to carefully read the label to make sure that the product actually contains Tabebuia avellanedae as an ingredient.
How to Take It
Do not give pau d'arco to infants or children.
It is important to discuss the dose with your health care provider, since large amounts of pau d'arco can be toxic. The risk of side effects seems to be greater when the dose of lapachol is more than 1.5 g per day. However, it can be hard to determine how much lapachol the powdered bark contains.
The use of herbs is a time honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.
Talk to your health care provider to determine the proper dose of pau d'arco because too much can be dangerous.
At recommended doses, side effects are uncommon but may include anemia, nausea, diarrhea, and dizziness.
High doses can cause uncontrolled bleeding and vomiting.
Pregnant and nursing women should not take pau d'arco.
Antiplatelet and anticoagulant drugs (blood thinners) -- Pau d'arco may affect the blood's ability to clot, and could interfere with any blood thinning drugs you are taking, including:
Anesini C, Perez C. Screening of plants used in Argentine folk medicine for antimicrobial activity. J Ethnopharmacol. 1993;39:119-128.
Byeon SE, Chung JY, Lee YG, Kim BH, Kim KH, Cho JY. In vitro and in vivo anti-inflammatory effects of taheebo, a water extract from the inner bark of Tabebuia avellanedae. J Ethnopharmacol. 2008 Sep 2;119(1):145-52.
Colman de Saizarbitoria T, Anderson JE, Alfonso D, McLaughlin JL. Bioactive furonaphtoquinones from Tabebuia barbata (Bignoniaceae). Acta Cient Venez. 1997;48(1):42-46.
de Miranda FG, Vilar JC, Alves IA, Cavalcanti SC, Antoniolli AR. Antinociceptive and antiedematogenic properties and acute toxicity of Tabebuia avellanedae Lor. ex Griseb. inner bark aqueous extract. BMC Pharmacol. 2001;1(1):6.
Dinnen RD, Ebisuzaki K. The search for novel anticancer agents: a differentiation-based assay and analysis of a folklore product. Anticancer Res. 1997;(2A):1027-1033.
Gomez Castellanos JR, Prieto JM, Heinrich M. Red Lapacho (Tabebuia impetiginosa) -- a global ethnopharmacological commodity? J Ethnopharmacol. 2009;121(1):1-13.
Kung HN, Yang MJ, Chang CF, Chau YP, Lu KS. In vitro and in vivo wound healing-promoting activities of beta-lapachone. Am J Physiol Cell Physiol. 2008 Oct;295(4):C931-43.
Lee JI, Choi DY, Chung HS, Seo HG, Woo HJ, Choi BT, Choi YH. Beta-lapachone induces growth inhibition and apoptosis in bladder cancer cells by modulation of Bcl-2 family and activation of caspases. Exp Oncol. 2006 Mar;28(1):30-5.
Machado TB, Pinto AV, Pinto MC, et al. In vitro activity of Brazilian medicinal plants, naturally occurring naphthoquinones and their analogues, against methicillin-resistant Staphylococcus aureus. International Journal of Antimicrobial Agents. 2003;21(3):279-284.
Muller K, Sellmer A, Wiegrebe W. Potential antipsoriatic agents: lapacho compounds as potent inhibitors of HaCaT cell growth. J Nat Prod. 1999;62(8):1134-1136.
Park BS, Lee HK, Lee SE, Piao XL, Takeoka GR, Wong RY, et al. Antibacterial activity of Tabebuia impetiginosa Martius ex DC (Taheebo) against Helicobacter pylori. J Ethnopharmacol. 2006 Apr 21;105(1-2):255-62.
Pereira EM, Machado Tde B, Leal IC, et al. Tabebuia avellanedae naphthoquinones: activity against methicillin-resistant staphylococcal strains, cytotoxic activity and in vivo dermal irritability analysis. Ann Clin Microbiol Antimicrob. 2006 March 22;5:5.
Pinto CN, Dantas AP, De Moura KC, et al. Chemical reactivity studies with naphthoquinones from Tabebuia with anti-trypanosomal efficacy. Arzneimittelforschung. 2000;50(12):1120-1128.
Portillo A, Vila R, Freixa B, Adzet T, Canigueral S. Antifungal activity of Paraguayan plants used in traditional medicine. J Ethnopharmacol.2001;76(1):93-98.
Robbers JE, Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press; 1999:246-247.
Ueda S, Umemura T, Dohguchi K, et al. Production of anti-tumour-promoting furanonaphthoquinones in Tabebuia avellanedae cell cultures. Phytochemistry. 1994;36:323-325.
Ipe roxo; LaPacho; Tabebuia avellanedae; Taheboo tree
- Last Reviewed on 04/03/2011
- Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
This page was last updated: May 7, 2013