Pau d'Arco: Uses, Benefits, Dosage & Safety
Last updated: June 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy
Quick summary
Pau d'arco is a South American tree bark marketed for immune and antifungal support. Human evidence is weak and high doses can be toxic.
What is Pau d'Arco?
Pau d'arco (Tabebuia/Handroanthus impetiginosus) is the inner bark of a South American tree, used traditionally and marketed for immune, antifungal and 'anti-Candida' support. Its compounds include lapachol.
What Pau d'Arco is commonly used for
In supplements, Pau d'Arco is most often included for skin & anti-aging, women's bladder & urinary health support. It is used as nutritional support, not as a treatment for any medical condition — the distinction matters, because the claims on a sales page are often stronger than the evidence allows.
How Pau d'Arco works
Lapachol and naphthoquinones in pau d'arco have antimicrobial and other activity in laboratory studies, the basis for its marketing, but these effects have not been confirmed as useful or safe in people at normal doses.
What the evidence says
Here's an honest snapshot of what published research suggests about Pau d'Arco — including where the evidence is limited.
- Human evidence for pau d'arco is lacking, and the active compounds that show laboratory activity also cause toxicity at the doses that would be needed.
- Study quality and doses vary, and a result seen in research doesn't guarantee the same for any individual — use the sources below to check the current evidence on Pau d'Arco rather than relying on marketing claims.
Typical dosage used in studies
Traditional teas and extracts vary; there is no established safe effective dose. This is general information from research, not a personal recommendation or a dosing instruction.
Side effects and safety
High doses of pau d'arco can cause nausea, bleeding and serious toxicity, and it may interact with blood thinners. It is avoided in pregnancy and used cautiously if at all. As with any supplement, it's sensible to introduce Pau d'Arco on its own, use a trusted brand, and stop if you notice any reaction.
Medication interactions and who should avoid Pau d'Arco
Medication & safety check
Herbs interact with prescription medicines more often than people expect — affecting drug levels, bleeding, blood pressure, blood sugar or sedation — and Pau d'Arco is no exception. If you take any regular medication, are pregnant or breastfeeding, or manage a health condition, confirm Pau d'Arco is appropriate for you before starting.
This is general information, not personal medical advice. If you take any medication, are pregnant or breastfeeding, or have a health condition, confirm it's safe to use Pau d'Arco with your doctor or pharmacist first.
Sources & further reading
For authoritative background and the current research base on Pau d'Arco, consult:
- PubMed — search the research on Pau d'Arco
- NCCIH — Herbs at a Glance
- MedlinePlus — herbs & supplements
- MedlinePlus — drugs, herbs & supplements
Frequently asked questions
Does Pau d'Arco actually work?
Human evidence for pau d'arco is lacking, and the active compounds that show laboratory activity also cause toxicity at the doses that would be needed. As with most supplements, results vary between people and the marketing is often stronger than the evidence — so it's worth checking the research before relying on it.
Is Pau d'Arco safe to take?
For most healthy adults at normal doses it's generally well tolerated, but there are real cautions. High doses of pau d'arco can cause nausea, bleeding and serious toxicity, and it may interact with blood thinners. It is avoided in pregnancy and used cautiously if at all. If you take medication, are pregnant or breastfeeding, or have a health condition, check with a doctor or pharmacist first.
What is Pau d'Arco used for?
In supplements, Pau d'Arco is mainly included for skin & anti-aging, women's bladder & urinary health support — as nutritional support, not as a treatment for any medical condition.
Where you'll find Pau d'Arco
On FactoWiki, Pau d'Arco is the kind of ingredient you'll see discussed in these supplement categories. Each category guide breaks down what the evidence does and doesn't support.
Related ingredients to explore
Ingredients often studied or formulated alongside Pau d'Arco — useful for understanding the full picture of a formula.