Pau d'arco is the Portuguese name for various species of tall, flowering, evergreen trees native to Brazil and other tropical parts of South and Central America. Herbal preparations are derived in particular from the inner bark of a tree also known to native Indians as lapacho and taheebo. Pau d'arco has been used for centuries in South America topically to heal wounds and taken orally to promote overall health and vigor. It has been used to help prevent or treat malaria, the common cold, flu, fever, and various digestive ailments.