Flowers of Pau d’Arco tree (Portuguese), Lapacho (Spanish) - Tabebuia spp. (Bignoniaceae)

Medicinal Use of Pau d’Arco (Portuguese), Lapacho (Spanish) – Tabebuia spp. (Bignoniaceae)

Bark from the pau d’arco tree has been valued for centuries in traditional South American herbal medicine for its remarkable health benefits. Today, it is given as a remedy for inflammatory and infectious problems, including conditions such as chronic fatigue and candidiasis. It is also used for other conditions and has a mixed reputation as a treatment for cancer, including leukemia.

Habitat & Cultivation

An indigenous South American tree, pau d’arco grows well in mountainous terrains. In Peru and Argentina it is found growing high up in the Andes. Pau d’arco is also found in low-lying areas (in Paraguay and Brazil), where it is thought to have originated.

Many Tabebuia species are used in herbal medicine, so quality control of dried bark can be difficult. T. avellanedae is considered to be the most therapeutic ally effective species, while T. impetignosa is the species that is most commonly available. Pau d’arco is not normally cultivated—the prized inner bark is collected from trees growing in the wild, throughout the year.

Key Constituents

  • Napthaquinones (lapachol)
  • Anthraquinones
  • Coumarins
  • Flavonoids
  • Iridoids
  • Carnosol

Key Actions

  • Antibacterial
  • Antifungal
  • Antiparasitic
  • Immunostimulant
  • Anti-inflammatory
  • Tonic
  • Antitumor


Antibacterial and anti-fungal activity: A Colombian review (2013) of research data on Tabebuia species, much of which was undertaken in South America, highlighted pau d’arco’s strong, direct activity against several key bacteria, notably Staphylococcus aureus and Helicobacter pylori, the latter being the principal cause of stomach ulcers. It also has broad-ranging activity against many fungal agents, including Candida albicans.

Antitumor properties: Pau d’arco’s anticancer action has been established in laboratory experiments, with many of its constituents suppressing the growth of cancer cells. Research in Brazil in the 1960s raised great hopes that pau d’arco might prove to be a major cancer treatment, but clinical research has failed to produce positive results.

Traditional & Current Uses

Early cure-all: The Incas, the Callawaya in Brazil, and other Native South American peoples all prized pau d’arco as a cure-all. They used it to treat a variety of conditions, including wounds, fever, dysentery, and intestinal inflammation, as well as certain types of cancer and snake bite.

Infections: Given the large number of active constituents in pau d’arco, it is not surprising that this beneficial herb is used in South America and by herbal practitioners throughout the world. It is an important, natural antibiotic for bacterial and viral infections, especially of the nose, mouth, and throat, and is considered helpful for chronic conditions such as CFS (chronic fatigue syndrome). Pau d’arco is also used for fungal conditions, including ringworm and thrush, and is considered especially useful for treating chronic candidiasis.

Anti-inflammatory action: Pau d’arco reduces and relieves inflammatory problems, especially in the stomach and intestines. It is used to treat a wide range of other inflammatory conditions, including cystitis, inflammation of the cervix, and prostatitis.

Cancer remedy: Clinical experience in Brazil, combined with its worldwide use by herbalists as a cancer remedy, suggests that pau d’arco may be beneficial in the treatment of cancer, including leukemia. However, more intensive research is needed into its therapeutic value.