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Pau D'arco

What is it?

Pau d'arco is a tree that grows in the Amazon rainforest. Pau d'arco wood is dense and resists rotting. The name "pau d'arco" is the Portuguese word for "bow stick," an appropriate term considering the tree's use by the native South American Indians for making hunting bows. The bark and wood are used to make medicine.

Though possibly unsafe, especially at higher doses, pau d'arco is used to treat a wide range of infections. These include viral respiratory infections such as the common cold, flu, and H1N1 (swine) flu; sexually transmitted infections such as gonorrhea and syphilis; infections of the prostate and bladder; ringworm and other parasitic infections; yeast infections; and infectious diarrhea.

Pau d'arco is also used for cancer. Interest in this use was intensified by extensive research in the 1960s that focused on the possible anti-cancer activity of lapachol, one of the chemicals in pau d'arco. However, research studies were stopped because, at the amounts needed to be effective against cancer, pau d'arco might well be poisonous. Among other things, it can cause severe internal bleeding.

Other uses for pau d'arco include diabetes, ulcers, stomach inflammation (gastritis), liver ailments, asthma, bronchitis, joint pain, hernias, boils, and wounds. Because some people see pau d'arco as a "tonic and blood builder," it is also used to treat anemia.

Pau d'arco is applied directly to the skin for Candida yeast infections.

Commercial products containing pau d'arco are available in capsule, tablet, extract, powder, and tea forms. But sometimes it's hard to know what is in pau d'arco products. Some studies have shown that some pau d'arco products sold in Canada and Brazil do not contain the active ingredients in the correct amounts.

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for PAU D'ARCO are as follows:

Insufficient evidence to rate effectiveness for...

  • Yeast infections.
  • Common cold.
  • Flu.
  • Diarrhea.
  • Bladder and prostate infections.
  • Intestinal worms.
  • Cancer.
  • Diabetes.
  • Ulcers.
  • Stomach problems.
  • Liver problems.
  • Asthma.
  • Bronchitis.
  • Arthritis-like pain.
  • Sexually transmitted diseases (gonorrhea, syphilis).
  • Boils.
  • Other conditions.
More evidence is needed to rate the effectiveness of pau d'arco for these uses.

How does it work?

Early research shows that pau d'arco might prevent cancer cells from growing. It might also slow tumor growth by preventing the tumor from growing the necessary blood vessels. However, the doses needed to cause anticancer effects seem to cause serious side effects in humans.

Are there safety concerns?

Pau d'arco is POSSIBLY UNSAFE when taken by mouth in typical doses. Talk with your healthcare provider before you decide to take it. Pau d'arco is LIKELY UNSAFE when taken by mouth in high doses. High doses can cause severe nausea, vomiting, diarrhea, dizziness, and internal bleeding.

Special precautions & warnings:

Pregnancy and breast-feeding: During pregnancy, pau d'arco is POSSIBLY UNSAFE when taken by mouth in typical amounts, and LIKELY UNSAFE in larger doses. Not enough is known about the safety of applying it to the skin. Stay on the safe side and avoid use if you are pregnant.

There is not enough reliable information available about the safety of taking pau d'arco if you are breast-feeding. Stay on the safe side and avoid use.

Bleeding disorders: Pau d'arco can delay clotting and might interfere with treatment in people with bleeding disorders.

Surgery: Pau d'arco might slow blood clotting and could increase the chance of bleeding during and after surgery. Stop using it at least 2 weeks before a scheduled surgery.

Are there interactions with medications?

Moderate
Be cautious with this combination.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Pau d'arco might slow blood clotting. Taking pau d'arco along with medications that also slow clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

Are there interactions with herbs and supplements?

Herbs and supplements that might slow blood clotting
Pau d'arco might slow blood clotting. Taking pau d'arco along with other herbs or supplements that also slow clotting might increase the chances of bruising and bleeding in some people. These herbs include alfalfa, angelica, clove, danshen, horse chestnut, red clover, turmeric, and others.

Are there interactions with foods?

There are no known interactions with foods.

What dose is used?

The appropriate dose of pau d'arco depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for pau d'arco. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Other names

Bignonia heptaphylla, Ébénier de Guyane, Ébène Vert, Handroanthus impetiginosus, Ipe, Ipe Roxo, Ipes, Lapacho, Lapacho Colorado, Lapacho Morado, Lébène, Pink Trumpet Tree, Purple Lapacho, Quebracho, Red Lapacho, Tabebuia avellanedae, Tabebuia heptaphylla, Tabebuia ipe, Tabebuia palmeri, Tabebuia impetiginosa, Taheebo, Taheebo Tea, Tecoma impetiginosa, Tecoma ipe, Thé Taheebo, Trumpet Bush.

Methodology

To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.

References

  1. Awang DVC. Commercial taheebo lacks active ingredient. Information Letter 726 Can Pharm J. 1991;121:323-26.
  2. Awang DVC, Dawson BA, Ethier J-C, et al. Naphthoquinone Constituents of Commercial Lapacho/Pau d'arco/Taheebo Products. J Herbs Spic Med Plants. 1995;2:27-43.
  3. Nepomuceno JC. Lapachol and its derivatives as potential drugs for cancer treatment. In: Plants and Crop - The Biology and Biotechnology Research, 1st ed. iConcept Press Ltd.. Retrieved from: https://www.researchgate.net/profile/Julio_Nepomuceno/publication/268378689_Lapachol_and_its_derivatives_as_potential_drugs_for_cancer_treatment/links/5469c8640cf20dedafd103e1.pdf.
  4. Paes JB, Morais VM, Lima CR. Resistência natural de nove madeiras do semi-árido brasileiro a fungos causadores da podridão-mole. R. Árvore, 2005;29:365-71.
  5. Kreher B, Lotter H, Cordell GA, Wagner H. New Furanonaphthoquinones and other Constituents of Tabebuia avellanedae and their Immunomodulating Activities in vitro. Planta Med. 1988 ;54:562-3. View abstract.
  6. de Almeida ER, da Silva Filho AA, dos Santos ER, Lopes CA. Antiinflammatory action of lapachol. J Ethnopharmacol. 1990 ;29:239-41. View abstract.
  7. Guiraud P, Steiman R, Campos-Takaki GM, Seigle-Murandi F, Simeon de Buochberg M. Comparison of antibacterial and antifungal activities of lapachol and beta-lapachone. Planta Med. 1994;60:373-4. View abstract.
  8. Block JB, Serpick AA, Miller W, Wiernik PH. Early clinical studies with lapachol (NSC-11905). Cancer Chemother Rep 2. 1974;4:27-8. View abstract.
  9. Kung, H. N., Yang, M. J., Chang, C. F., Chau, Y. P., and Lu, K. S. In vitro and in vivo wound healing-promoting activities of beta-lapachone. Am.J Physiol Cell Physiol 2008;295:C931-C943. View abstract.
  10. Byeon, S. E., Chung, J. Y., Lee, Y. G., Kim, B. H., Kim, K. H., and Cho, J. Y. In vitro and in vivo anti-inflammatory effects of taheebo, a water extract from the inner bark of Tabebuia avellanedae. J Ethnopharmacol. 9-2-2008;119:145-152. View abstract.
  11. Twardowschy, A., Freitas, C. S., Baggio, C. H., Mayer, B., dos Santos, A. C., Pizzolatti, M. G., Zacarias, A. A., dos Santos, E. P., Otuki, M. F., and Marques, M. C. Antiulcerogenic activity of bark extract of Tabebuia avellanedae, Lorentz ex Griseb. J Ethnopharmacol. 8-13-2008;118:455-459. View abstract.
  12. Queiroz, M. L., Valadares, M. C., Torello, C. O., Ramos, A. L., Oliveira, A. B., Rocha, F. D., Arruda, V. A., and Accorci, W. R. Comparative studies of the effects of Tabebuia avellanedae bark extract and beta-lapachone on the hematopoietic response of tumour-bearing mice. J Ethnopharmacol. 5-8-2008;117:228-235. View abstract.
  13. Savage, R. E., Tyler, A. N., Miao, X. S., and Chan, T. C. Identification of a novel glucosylsulfate conjugate as a metabolite of 3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione (ARQ 501, beta-lapachone) in mammals. Drug Metab Dispos. 2008;36:753-758. View abstract.
  14. Bohler, T., Nolting, J., Gurragchaa, P., Lupescu, A., Neumayer, H. H., Budde, K., Kamar, N., and Klupp, J. Tabebuia avellanedae extracts inhibit IL-2-independent T-lymphocyte activation and proliferation. Transpl.Immunol. 2008;18:319-323. View abstract.
  15. Yamashita, M., Kaneko, M., Iida, A., Tokuda, H., and Nishimura, K. Stereoselective synthesis and cytotoxicity of a cancer chemopreventive naphthoquinone from Tabebuia avellanedae. Bioorg.Med Chem.Lett. 12-1-2007;17:6417-6420. View abstract.
  16. Kim, S. O., Kwon, J. I., Jeong, Y. K., Kim, G. Y., Kim, N. D., and Choi, Y. H. Induction of Egr-1 is associated with anti-metastatic and anti-invasive ability of beta-lapachone in human hepatocarcinoma cells. Biosci Biotechnol Biochem 2007;71:2169-2176. View abstract.
  17. de Cassia da Silveira E Sa and de Oliveira, Guerra M. Reproductive toxicity of lapachol in adult male Wistar rats submitted to short-term treatment. Phytother.Res. 2007;21:658-662. View abstract.
  18. Kung, H. N., Chien, C. L., Chau, G. Y., Don, M. J., Lu, K. S., and Chau, Y. P. Involvement of NO/cGMP signaling in the apoptotic and anti-angiogenic effects of beta-lapachone on endothelial cells in vitro. J Cell Physiol 2007;211:522-532. View abstract.
  19. Woo, H. J., Park, K. Y., Rhu, C. H., Lee, W. H., Choi, B. T., Kim, G. Y., Park, Y. M., and Choi, Y. H. Beta-lapachone, a quinone isolated from Tabebuia avellanedae, induces apoptosis in HepG2 hepatoma cell line through induction of Bax and activation of caspase. J Med Food 2006;9:161-168. View abstract.
  20. Son, D. J., Lim, Y., Park, Y. H., Chang, S. K., Yun, Y. P., Hong, J. T., Takeoka, G. R., Lee, K. G., Lee, S. E., Kim, M. R., Kim, J. H., and Park, B. S. Inhibitory effects of Tabebuia impetiginosa inner bark extract on platelet aggregation and vascular smooth muscle cell proliferation through suppressions of arachidonic acid liberation and ERK1/2 MAPK activation. J Ethnopharmacol. 11-3-2006;108:148-151. View abstract.
  21. Lee, J. I., Choi, D. Y., Chung, H. S., Seo, H. G., Woo, H. J., Choi, B. T., and Choi, Y. H. beta-lapachone induces growth inhibition and apoptosis in bladder cancer cells by modulation of Bcl-2 family and activation of caspases. Exp.Oncol. 2006;28:30-35. View abstract.
  22. Pereira, E. M., Machado, Tde B., Leal, I. C., Jesus, D. M., Damaso, C. R., Pinto, A. V., Giambiagi-deMarval, M., Kuster, R. M., and Santos, K. R. Tabebuia avellanedae naphthoquinones: activity against methicillin-resistant staphylococcal strains, cytotoxic activity and in vivo dermal irritability analysis. Ann.Clin.Microbiol.Antimicrob. 2006;5:5. View abstract.
  23. Felicio, A. C., Chang, C. V., Brandao, M. A., Peters, V. M., and Guerra, Mde O. Fetal growth in rats treated with lapachol. Contraception 2002;66:289-293. View abstract.
  24. Guerra, Mde O., Mazoni, A. S., Brandao, M. A., and Peters, V. M. Toxicology of Lapachol in rats: embryolethality. Braz.J Biol. 2001;61:171-174. View abstract.
  25. Lemos OA, Sanches JC, Silva IE, et al. Genotoxic effects of Tabebuia impetiginosa (Mart. Ex DC.) Standl. (Lamiales, Bignoniaceae) extract in Wistar rats. Genet Mol Biol 2012;35:498-502. View abstract.
  26. Kiage-Mokua BN, Roos N, Schrezenmeir J. Lapacho Tea (Tabebuia impetiginosa) Extract Inhibits Pancreatic Lipase and Delays Postprandial Triglyceride Increase in Rats. Phytother Res 2012 Mar 17. doi: 10.1002/ptr.4659. View abstract.
  27. de Melo JG, Santos AG, de Amorim EL, et al. Medicinal plants used as antitumor agents in Brazil: an ethnobotanical approach. Evid Based Complement Alternat Med 2011;2011:365359. Epub 2011 Mar 8. View abstract.
  28. Gómez Castellanos JR, Prieto JM, Heinrich M. Red Lapacho (Tabebuia impetiginosa)--a global ethnopharmacological commodity? J Ethnopharmacol 2009;121:1-13. View abstract.
  29. Park BS, Lee HK, Lee SE, et al. Antibacterial activity of Tabebuia impetiginosa Martius ex DC (Taheebo) against Helicobacter pylori. J Ethnopharmacol 2006;105:255-62. View abstract.
  30. Park BS, Kim JR, Lee SE, et al. Selective growth-inhibiting effects of compounds identified in Tabebuia impetiginosa inner bark on human intestinal bacteria. J Agric Food Chem 2005;53:1152-7. View abstract.
  31. Koyama J, Morita I, Tagahara K, Hirai K. Cyclopentene dialdehydes from Tabebuia impetiginosa. Phytochemistry 2000;53:869-72. View abstract.
  32. Park BS, Lee KG, Shibamoto T, et al. Antioxidant activity and characterization of volatile constituents of Taheebo (Tabebuia impetiginosa Martius ex DC). J Agric Food Chem 2003;51:295-300. View abstract.
Last reviewed - 07/20/2016