Pau d'arco
Handroanthus impetiginosus (Mart. ex DC.) MattosBignoniaceae // inner bark
Overview
Plant parts
inner bark
Known constituents
lapachol, beta-lapachone, naphthoquinones
Research corpus coverage
Chemistry notes
- CHEMISTRY: Relevant reported constituents include lapachol; beta-lapachone; naphthoquinones; constituent presence alone does not establish clinical efficacy.
Uses & Evidence
Traditional / historical use
Documented traditional use — not a claim of established efficacy.
TRADITIONAL: Pau d'arco has been used for infections; inflammation; cancer claims; this records historical/traditional use and does not establish efficacy.
MODERATE · regulatory monograph · WHO Monographs on Selected Medicinal Plants
Modern evidence
EVIDENCE: For the major use set (infections; inflammation; cancer claims), the evidence assessment is insufficient: Insufficient clinical evidence; anticancer claims are unsupported by human trials.
LOW · randomized controlled trial · WHO Monographs on Selected Medicinal Plants
Preparation
Forms used traditionally
A listed form does not imply it suits every plant part, or that one preparation is interchangeable with another — see the plant’s own notes below.
PREPARATION: The medicinal material is inner bark; traditional and modern forms include decoction, tincture, powder/capsule, standardized extract. No dose or potency is specified.
MODERATE · regulatory monograph · EMA European Union herbal monographs and list entries
Preparation-specific evidence should not be generalized across extracts, teas, oils, or whole herb.
Safety
Additional safety notes (general, unstructured)
Free-text safety notes carried from their source — not broken out by species, route, or hazard type, and not equivalent to the structured records above. Each note names the kind of source it came from.
SAFETY: Major issues include GI toxicity, anemia and bleeding at higher exposures. Contraindications/cautions include Pregnancy; bleeding disorders.
HIGH · observational/case series and expert review · LiverTox: Herbal and Dietary Supplements
SAFETY: Clinically relevant interaction concerns include Additive anticoagulant/antiplatelet effects.
MODERATE · observational/case series and expert review · LiverTox: Herbal and Dietary Supplements
Some interactions are theoretical or based on case reports/pharmacokinetics rather than outcome trials.
SAFETY: Pregnancy/lactation reference: Avoid in pregnancy/lactation.
MODERATE · regulatory monograph or evidence synthesis · WHO Monographs on Selected Medicinal Plants
Absence of evidence is not evidence of safety.
Preparation × species risk matrix
Unknown means insufficient evidence was located — not that a form is safe.
Cats
- tinctureCaution
- concentrated extractUnknown
- essential oilUnknown
- glyceriteUnknown
- infused oilUnknown
- salveUnknown
- smoke/combustionUnknown
- tea/infusionUnknown
- whole herbUnknown
Dogs
- tinctureCaution
- concentrated extractUnknown
- essential oilUnknown
- glyceriteUnknown
- infused oilUnknown
- salveUnknown
- smoke/combustionUnknown
- tea/infusionUnknown
- whole herbUnknown
Identity
- Synonym
GBIF resolves Tabebuia impetiginosa (Mart. ex A.DC.) Standl. as a synonym of Handroanthus impetiginosum. The older name still appears in herbal and taxonomic literature.
HIGH · GBIF Species Match API
Botanical synonym
Tabebuia impetiginosa (Mart. ex DC.) Standl.
Taxonomic identity note
- Pau d'arco is treated here as Handroanthus impetiginosus (Mart. ex DC.) Mattos in the family Bignoniaceae; recorded older names include Tabebuia impetiginosa (Mart. ex DC.) Standl..
Sources
Research records are source-linked but may not yet be editorially reviewed.
WHO monograph
NIH LiverTox monograph
- Plants of the World Online1 claim
botanical taxonomy database
EMA monograph
- GBIF Species Match API1 claim
authoritative taxonomic database