Pau d'arco, or the inner bark of the Tabebuia avellanedae tree, is native to Brazil, where it is used traditionally to treat a wide range of conditions including pain, arthritis, inflammation of the prostate gland (prostatitis), fever, dysentery, boils and ulcers, and various cancers. Preliminary laboratory research examining the properties of pau d'arco is beginning to suggest that the traditional uses may have scientific merit. Such laboratory studies have shown that pau d'arco has pain killing, diuretic, anti-inflammatory, anti-infectious, anti-psoriatic, and anti-cancer abilities. Taking this early data, combined with information collected about traditional uses, herbalists may recommend pau d'arco to treat or prevent a number of conditions, including candidiasis (a yeast infection of the vaginal or oral areas), herpes simplex virus, influenza, parasitic diseases such as schistosomiasis, bacterial infections such as brucellosis, and inflammation of the cervix (cervicitis) or the vagina (vaginitis). Pau d'arco may also reduce inflammation of the joints associated with arthritis.

The Tabebuia evergreen tree grows in the warm parts of Central and South America. Most pau d'arco comes from a tree in the Amazon rain forest called Tabebuia avellanedae. It is a broad-leaf evergreen that grows to a height of 125 feet and is distinguished by pink to violet colored flowers. Its extremely hard wood makes it resistant to disease and decay. In recent years, however, there has been an increasing demand for pau d'arco and, as a result, the trees are in danger of becoming extinct.

Most of the chemical research on pau d'arco has been done on the wood and not the bark, although it is in fact the inner bark that has been used traditionally for medicinal purposes. In addition, there are a variety of Tabebuia species that have been tested for anti-infectious and anti-cancer properties, not only avellanedae. Therefore, it is difficult to know at this point what findings apply specifically to pau d'arco and which apply to other species of this plant. The heartwood of Tabebuia avellanedae contains chemical compounds called naphthoquinones such as lapachol, as well as significant amounts of the antioxidant quercetin.

Pau d'arco is sold as dried bark tea, alcohol extract, and nonalcohol (usually glycerin) extract. Most pau d'arco products are not standardized, however, therefore, it is not possible to determine whether or not they contain a consistent or appropriate amount of these active substances.

Some herbal teas that are labeled with pau d'arco are not actually made from Tabebuia trees. It is important to carefully read the label to make sure that the product actually contains Tabebuia avellanedae as an ingredient.

Pediatric

There are no known scientific reports on the pediatric use of pau d'arco. Therefore, this herb is not currently recommended for children.

Adult

• Decoction (tea): Using 1 tsp of pau d'arco loose dried bark per 1 cup water, boil for 5 to 15 minutes. Drink 1 cup of this tea two to eight times a day.
• Extract: Follow the directions on the product label.
• Tincture (1:5): Solution made from herb and alcohol, or herb, alcohol, and water—take 20 to 30 drops, two to three times per day.
• Capsules: 1,000 mg three times per day.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

It is generally safe to drink pau d'arco tea and take pau d'arco extract at the recommended dosages. Too much, however, may cause nausea.

There are no reports in the scientific literature to suggest that pau d'arco interacts with any conventional medications.

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