Commonly known as LaPacho in Brazil, where it is native, Pau D'Arco (Tabebuia avellanedae) is now fairly popular as a supplement ingredient in the United States. There are about 100 species of similar plants in the tropics of the Americas, only a few of which have the activities described here. The heartwood, or inner bark contains as many as 16 quinone compounds, the best studied and most active components of Pau D'Arco. Lapachol, one of the best-studied naphthoquinones in Pau D'Arco, is usually present at between 2-7%.
Lapachol, as well as the whole extract, has been shown to be antimicrobial against a wide range of infection organisms. Several of the quinones have proven to also have antiviral, antiparasitic, antineoplastic and anti-inflammatory activities. With these activities, the use of Pau D' Arco is quite broad.
LaPacho bark can be boiled in water and used as a soak for toenail and fingernail fungus.