Pau D’Arco

Tabebuia avellanedae is a tropical evergreen tree growing to 30m height, native to Brazil, also known as lapacho and ipe-roxo. There is some confusion between the Tabebuia and Tecoma genera in the literature, and this is compounded by the fact that many of the studies and chemical analyses have been carried out on heart wood, while traditionally but also commercially it is the bark that is used. The major constituents of pau d’arco are seven naphthoquinones and nine anthraquinones, a rare occurrence of both these two groups of quinones in the same tree. Other compounds of the heart wood are lapachenole, quercetin, o- and p-hydroxybenzoic acids, quechua, etc.

  • Anti-bacterial. Several studies have shown that some of the quinones in pau d’arco possess powerful anti-bacterial and fungicidal activity. Naphthoquinones were found to be particularly effective against Candida albicans and Trichophyton mentagrophytes, a species of fungi causing ringworm infections. Naturally, the herb has become one of the most popular natural treatments of Candida infections.
  • Anti-parasitic. The naphthoquinone lapachol has been shown to possess both anti-microbial and anti-viral activity (see below). Thus alpha-lapachone is active against several parasites, while xyloidone is active against numerous bacteria and fungi, including Staphyloccocus aureus, the Brucella species toxic to both humans and domesticated animals, the pathogens of anthrax, dysentery and tuberculosis, and the fungi Candida albicans, C kruzei and C neoformans. Still another lapacho ingredient, the flavonoid quercetin, is also cytotoxic for certain parasites.
  • Anti-viral. To the anti-parasitic activity of alpha-lapachone, one should add the anti-parasitic and anti-viral activity of beta-lapachone, against herpes, four influenza viruses, poliovirus, and vesicular stomatitis virus. The anti-viral action of beta-lapachone seems to involve the inhibition of certain enzymes, such as DNA and RNA polymerases, linked to the production of superoxide, acting on the enzyme protein.

Caution. Not recommended in cases of excessive bleeding, or when taking prescribed anti-coagulants such as warfarin.