Pau D’Arco is the common name for the inner bark of several tree species native to the Amazon rainforest and other tropical regions of Central and South America. The most commonly studied species are Tabebuia impetiginosa and Tabebuia avellanedae, also known as Taheebo, Lapacho, and Ipe Roxo. This botanical material, which is the inner lining of the bark (phloem), comes from large, flowering trees. While it has gained modern attention as a dietary supplement, its use as a healing agent extends back for centuries.
Historical and Traditional Applications
The bark of the Pau D’Arco tree holds a significant place in the traditional medicine systems of indigenous South American cultures, including the Incas and the Callawaya people of Brazil. These groups traditionally used the inner bark for a wide variety of health concerns, establishing its reputation as a comprehensive folk remedy. They brewed the material into a strong tea or decoction to address internal ailments such as fever, intestinal inflammation, and dysentery.
Pau D’Arco was also applied topically to treat wounds, skin diseases, and snakebites. Historically, the bark was relied upon for treating various infections, including parasitic diseases.
Primary Mechanisms of Action
The biological effects attributed to Pau D’Arco are linked to a potent class of compounds within the inner bark called naphthoquinones. The two most prominent of these compounds are lapachol and beta-lapachone, which are believed to drive most of the material’s recognized activities. Laboratory studies have shown that these naphthoquinones possess anti-microbial properties, demonstrating an ability to inhibit the growth of various bacteria and fungi, including Candida species.
The mechanism of action involves disrupting the metabolism and cell membranes of these microorganisms, which contributes to Pau D’Arco’s anti-fungal properties. Beyond its effects on pathogens, the bark’s extracts have also shown anti-inflammatory activity in research models. This effect occurs through the suppression of pro-inflammatory molecules, such as COX-2 and PGE2, similar to the action of some anti-inflammatory medications. While laboratory and animal studies are promising, evidence from human clinical trials remains limited, and the effective concentration required may exceed safe levels for human consumption.
Modern Consumption and Safety Profile
Pau D’Arco is consumed today in several forms, including capsules, tinctures, and the traditional decoction, or tea. The traditional tea requires a specific process, known as decoction, to extract the active compounds from the dense bark. This involves simmering the inner bark material (typically a few tablespoons) in boiling water for 15 to 25 minutes before straining and drinking.
Despite its popularity, Pau D’Arco has a safety profile that requires careful consideration. In high doses, the active compounds can cause adverse effects, including severe nausea, vomiting, and dizziness. High concentrations also carry a risk of internal bleeding, which has limited its development in conventional medicine.
Because Pau D’Arco may slow blood clotting, it is not recommended for individuals taking anticoagulant or antiplatelet medications (such as warfarin or aspirin). It is also contraindicated for those who are pregnant or breastfeeding due to a lack of safety data and potential reproductive toxicity seen in animal studies. Anyone considering using Pau D’Arco should consult a healthcare provider to ensure it is appropriate and to discuss proper dosing, as the safety of typical doses is not fully established.