Historical or traditional use (may or may not be supported by scientific studies): Native peoples in Central and South America reportedly use pau d’arco bark to treat cancer, lupus, infectious diseases, wounds, and many other health conditions.1 Caribbean folk healers use the leaf of this tree in addition to the bark for the treatment of backache, toothache, sexually transmitted diseases, and as an aphrodisiac.
Active constituents: Lapachol and beta-lapachone (known collectively as naphthaquinones) are two primary active compounds in pau d’arco. According to laboratory tests, both have antifungal properties as potent or more so than ketaconazole, a common antifungal drug.2 Although these compounds also have anticancer properties, the effective dosage for this effect is toxic.3 4 Therefore, pau d’arco cannot currently be recommended as a treatment for cancer. Human studies are lacking to confirm the efficacy of pau d’arco.
How much is usually taken? A traditional dosage is 2–3 US teaspoons (15–20 grams) of the inner bark simmered in a pint of water for fifteen minutes. Then taken in three daily doses.5 Capsules or tablets providing 300 mg of powdered bark can be taken; usually three capsules are ingested three times per day. A tincture can be used in the amount of 0.5–1 ml three times per day.
Are there any side effects or interactions? High amounts (several grams daily over several days) of lapachol can cause uncontrolled bleeding, nausea, and vomiting.6 Use of the whole bark is much safer than isolated lapachol—the whole bark has no known serious side effects.7 Pregnant or lactating women should avoid use of pau d’arco.
At the time of writing, there were no well-known drug interactions with Pau D’arco.
References:
1. Duke JA. CRC Handbook of Medicinal Herbs. Boca Raton, FL: CRC
Press, 1985, 470–71.
2. Guiraud P, Steiman R, Campos-Takaki GM, et al. Comparison of antibacterial
and antifungal activities of lapachol and beta-lapachone. Planta Med
1994;60:373–74.
3. Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals.
Binghamton, NY: Pharmaceutical Products Press, 1994, 180.
4. Oswald EH. Lapacho. Br J Phytother 1993/4;3:112–17.
5. Foster S. Herbs for Your Health. Loveland, CO: Interweave Press,
1996, 70–71.
6. Duke JA. CRC Handbook of Medicinal Herbs. Boca Raton, FL: CRC Press,
1985, 470–71.
7. Oswald EH. Lapacho. Br J Phytother 1993/4;3:112–17.
