
Ipe-Roxo, lapacho, purple lapacho, trumpet bush and taheebo
Pau D'arco is a tree native to South America, preparations derived from the bark of which have been traditionally used to treat bacterial, fungal, viral infections, and cancer. Quinones, the main constituents, were shown to be the active principle of Pau D'arco (11) (12) (13) (14).
In vitro and in vivo studies of compounds isolated from Pau D'arco demonstrated antibacterial (3) (4) (5) (6), antifungal (7), antipsoriatic (8), immunomodulatory (9) (10), anti-inflammatory (19), antidepressant (20), anticancer (11) (12) (13) (14), and antimetastatic (14) properties. One of the compounds may also be effective against inflammatory disorders (24). A Pau D'arco extract selectively inhibits growth of ER positive breast cancer cells (21). Human studies are needed to validate these effects.
In a small single-arm study, Lapachol, a naphthoquinone isolated from the tree bark, failed to show any effects on patients with non-leukemic tumors or CML (chronic myelocytic leukemia) (15).
Reported adverse events from use of Pau D'arco include nausea, vomiting, dizziness and anemia (16). It may also enhance the activity of anticoagulants (17).
The anticancer activity of beta-lapachone, a quinone compound isolated from Pau D'arco, may be due to down regulation of COX-2 (cyclooxygenase) and telomerase activities (11). Beta-lapachone also induces apoptosis in cancer cells via mitochondrial-signaling (12) or by activating caspases (3) (9) (18). The anti-metastatic activity of beta-lapachone was shown to be through decreasing the invasive ability of cancer cells by inducing Egr-1 that is known to suppress metastasis (14).
Some constituents may have toxic effects. The effectiveness of Pau d'arco for the treatment of cancer in humans remains unproven.
Bottom Line: Pau D'arco has antibacterial and anticancer activities in laboratory studies, but these effects have not been shown in humans.
Pau D'arco, a tree native to South America, has been used in traditional medicine for a wide range of ailments. In laboratory studies, compounds extracted from Pau d'arco showed antibacterial, antifungal, anti-inflammatory, antidepressant, and anticancer properties. However, the safety and effectiveness of these compounds has not been tested in humans.