An inhabitant of the tropical rain forest, Pau d'Arco is a majestic tree that often reaches 125 feet in height. It owes its medicinal value to certain compounds in the bark. Called naphthaquinones, these substances show potent antifungal properties in laboratory tests. Indeed, they appear to outperform the common prescription antifungal drug ketoconazole (Nizoral).
In Latin America, where Pau d'Arco is grown, people use this herb to treat cancer, lupus, infectious diseases, wounds, and a variety of other ailments. In the Caribbean, it is considered a remedy for backache, toothache, sexually transmitted diseases, and low sexual drive. However, only its anti-infective properties have been verified.
Pau d'arco is promoted as a cure for dozens of illnesses and medical conditions, including arthritis, ulcers, diabetes, and cancer. Proponents also claim that when taken internally, it relieves infections, reduces inflammation, promotes digestion, strengthens the immune system, flushes toxins from the body, and protects against cardiovascular disease and high blood pressure. They also use it to treat lupus, osteomyelitis, Parkinson's disease, psoriasis, and to relieve pain. Applied externally, practitioners have used it to treat skin inflammation, fungal infections, hemorrhoids, eczema, and wounds.
Pau d'arco contains at least 20 other active compounds, including quercetin and other flavonoids, whose effects are not yet known. Unconfirmed tests showed that crude extracts of the tree bark stimulated activity of certain immune system cells (macrophages). The substance also killed lung cancer cells grown in culture and reduced the rate of lung metastases in mice who had undergone surgery to remove the initial tumor. The bark extract also may work to kill bacteria or fungi. Extracted compounds are not the same as the raw bark. One of the active ingredients in pau d'arco that has been studied is called lapachol. In laboratory animals, lapachol was found to be effective against malaria and certain kinds of animal tumor cells, such as sarcoma, but did not have an effect against other kinds of cancer, including leukemia and adenocarcinoma. Animal and laboratory studies may show a substance has certain effects, but further studies are necessary to determine if the results apply to humans.
Research has shown that it contains a natural antibacterial agent, has a healing effect on the entire body, cleanses the blood, and kills viruses. Pau d Arco builds the immune system and nerves, and increases resistance to disease. It is used for AIDS, allergies, all infections and inflammations, anemia, asthma, arthritis, arteriosclerosis, as a blood builder, bronchitis, all types of cancer, candidiasis, colitis, cystitis, smoker's cough, diabetes, eczema, paralysis of the eyelids, fistulas, gastritis, gonorrhea, hemorrhages, hernias, Hodgkins' disease, liver disease, leukemia, lupus, malaria, multiple sclerosis, nephritis, osteomyelitis, pain, Parkinsons' disease, polyps, prostatitis, psoriasis, pyorrhea, rheumatism, ringworm, skin cancer, skin sores, spleen infections, snake bites, ulcers including varicose ulcers, varicose veins, warts, wounds.