Pau d’arco is an herb found in the rainforests of the Amazon and in South and Latin America. Pau d’arco bark has been used by indigenous Latin populations for centuries to address a spectrum of health problems and today its strong resistance to harmful organisms is still appreciated. Pau d’arco is commonly used to support indications of allergies, liver problems, and candida and yeast infections.
How Does Pau D’Arco Work?
Pau d’arco contains compounds called quinoids, benzenoids, and flavonoids which have shown biological activity against harmful organisms. Additionally, a significant amount of pau d’arco’s benefits stem from its lapachol content. Lapachol is a compound known by the U.S department of Agriculture to be toxic and resistant to nearly all types of harmful organisms.
Pau d’arco contains another chemical, beta-lapachone, which, in lab studies, has demonstrated toxicity to harmful organisms, similar to lapachol.
Benefits of Pau D’Arco
Pau d’arco has been used as a traditional medicine for more than 1,500 years. Multiple studies have substantiated this use and shown pau d’arco to accelerate the healing of skin wounds and protect against staph infection.    Extracts of pau d’arco have been labeled as new therapies for ailments that produce redness and swelling.  The US Department of Agriculture’s Western Regional Research Center found pau d’arco to exhibit antioxidative activity.  Some research suggests that Pau d’arco may help the fight against serious health ailments . 
Pau D’Arco and Harmful Organisms
The increase of drug resistant strains has piqued the attention of the scientific community who have begun studying therapeutic plants as alternative options. Pau d’arco, which has been traditionally used by Latino and Haitian populations to fight infections, has been the subject of much interest.  
Researchers have observed activity of pau d’arco against candida.  Pau d’arco may provide relief for vaginitis, which is caused by candida, by way of therapeutic douching.  This was substantiated by researchers in Spain and Brazil who reported observing a similar toxicity to fungi and yeasts.  
Researchers at the College of Medicine at the University of Ibadan in Nigeria noted that extracts of pau d’arco displayed activity against harmful organisms.  Pau d’arco is one of several herbs to spark interest for potential to address various infections.  
Supplementing with Pau D’Arco
Few side effects have been linked to pau d’arco although upset stomach and nausea may occur with very high servings. Additionally, people who are taking blood thinners should consult their healthcare provider. Pau d’arco should not be used during pregnancy!
Many Pau d’arco supplements are low quality with little to no lapachol content. Before investing in any supplement containing pau d’arco, research the source it came from and make sure the inner bark, which is the most potent part of the tree, has been used. As always, only use supplements that are organically grown under quality conditions that are verifiable.
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