Pau d’arco (Tabebuia impetiginosa) is a tree that is native to the Amazon. Its bark and wood have been used for many conditions, but with little evidence.

The pau d’arco tree is used by native peoples in the regions where it grows for making hunting bows. The name “pau d’arco” is Portuguese for “bow tree.” Pau d’arco bark and wood might prevent cancer cells from growing and slow tumor growth. But the doses needed to cause these effects seem to be unsafe.

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

Pau d’arco is sometimes called quebracho. Don’t confuse this with a different plant called Quebracho Blanco. These are not the same.

There is interest in using pau d’arco for a number of purposes, but there isn’t enough reliable information to say whether it might be helpful.

When taken by mouth: Pau d’arco is possibly unsafe. In high doses, a chemical found in 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.

When applied to the skin: There isn’t enough reliable information to know if pau d’arco is safe to use or what the side effects might be.

Special precautions & warnings:

Pregnancy: Pau d’arco is possibly unsafe when taken by mouth. There isn’t enough reliable information to know if pau d’arco is safe when applied to the skin during pregnancy. Stay on the safe side and avoid any use.

Breast-feeding: There isn’t enough reliable information to know if pau d’arco is safe to use when 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.

Moderate

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 risk of bruising and bleeding.

Herbs and supplements that might slow blood clotting

Pau d’arco might slow blood clotting and increase the risk of bleeding. Taking it with other supplements with similar effects might increase the risk of bleeding in some people. Examples of supplements with this effect include garlic, ginger, ginkgo, nattokinase, and Panax ginseng.

There are no known interactions with foods.

There isn’t enough reliable information to know what an appropriate dose of pau d’arco might be. Some products containing pau d’arco, including capsules, tablets, extracts, powders, and teas, have been found to be mislabeled and adulterated. Be sure to consult a healthcare professional before using.

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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