URL of this page: https://medlineplus.gov/druginfo/natural/647.html

Pau D'Arco

What is it?

Pau d'arco is a tree that grows in the Amazon rainforest and other tropical regions of South and Central America. Pau d'arco wood is dense and resists rotting. The name "pau d'arco" is Portuguese for "bow tree," an appropriate term considering the tree's use by the native peoples of South America for making hunting bows. The bark and wood are used to make medicine.

People use pau d'arco for conditions such as infections, cancer, diabetes, stomach ulcers, and many others, but there is no good scientific evidence to support these uses. Using pau d'arco can also be unsafe, especially at higher doses.

Commercial products containing pau d'arco are available in capsule, tablet, extract, powder, and tea forms. But sometimes it's hard to know what is in pau d'arco products. Some studies have shown that some pau d'arco products sold in Canada, Brazil, and Portugal do not contain the active ingredients in the correct amounts.

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for PAU D'ARCO are as follows:

Insufficient evidence to rate effectiveness for...

  • Anemia.
  • Arthritis-like pain.
  • Asthma.
  • Bladder and prostate infections.
  • Boils.
  • Bronchitis.
  • Cancer.
  • Common cold.
  • Diabetes.
  • Diarrhea.
  • Eczema.
  • Fibromyalgia.
  • Flu.
  • Infections with yeast, bacteria, viruses, or parasites.
  • Intestinal worms.
  • Liver problems.
  • Psoriasis.
  • Sexually transmitted diseases (gonorrhea, syphilis).
  • Stomach problems.
  • Other conditions.
More evidence is needed to rate the effectiveness of pau d'arco for these uses.

How does it work?

Early research shows that pau d'arco might prevent cancer cells from growing. It might also slow tumor growth by preventing the tumor from growing the necessary blood vessels. However, the doses needed to cause anticancer effects seem to cause serious side effects in humans.

Are there safety concerns?

Pau d'arco is POSSIBLY UNSAFE when taken by mouth. In high doses, pau d'arco can cause severe nausea, vomiting, diarrhea, dizziness, and internal bleeding. The safety of pau d'arco in typical doses is not known.

Special precautions & warnings:

Pregnancy and breast-feeding: During pregnancy, pau d'arco is POSSIBLY UNSAFE when taken by mouth in typical amounts, and LIKELY UNSAFE in larger doses. Not enough is known about the safety of applying it to the skin. Stay on the safe side and avoid use if you are pregnant.

There is not enough reliable information available about the safety of taking pau d'arco if you are breast-feeding. Stay on the safe side and avoid use.

Surgery: Pau d'arco might slow blood clotting and could increase the chance of bleeding during and after surgery. Stop using it at least 2 weeks before a scheduled surgery.

Are there interactions with medications?

Be cautious with this combination.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Pau d'arco might slow blood clotting. Taking pau d'arco along with medications that also slow clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

Are there interactions with herbs and supplements?

Herbs and supplements that might slow blood clotting
Pau d'arco might slow blood clotting. Taking pau d'arco along with other herbs or supplements that also slow clotting might increase the chances of bruising and bleeding in some people. These herbs include alfalfa, angelica, clove, danshen, horse chestnut, red clover, turmeric, and others.

Are there interactions with foods?

There are no known interactions with foods.

What dose is used?

The appropriate dose of pau d'arco depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for pau d'arco. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Other names

Ébénier de Guyane, Ébène Vert, Handroanthus impetiginosus, Ipe, Ipe Roxo, Ipes, Lapacho, Lapacho Colorado, Lapacho Morado, Lapacho Negro, Lébène, Pink Trumpet Tree, Purple Lapacho, Quebracho, Red Lapacho, Tabebuia avellanedae, Tabebuia heptaphylla, Tabebuia impetiginosa, Tabebuia palmeri, Taheebo, Taheebo Tea, Tecoma impetiginosa, Thé Taheebo, Trumpet Bush.


To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.


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Last reviewed - 08/16/2018