Pau D'Arco/ Taheebo Tea/ Lapacho/ Lapacho Morado/ Ipe Roxo/ Ipe/ Trumpet Bush
The role of your cancer health professional is to create an environment of openness and trust, and to help in making informed decisions about alternative/ complementary therapies. Collaboration will improve the safe integration of all therapies during your experience with cancer. The "Summary" and "Professional Evaluation/ Critique" sections of this Unconventional Therapies manual are cited directly from the medical literature, and are intended to help in the objective evaluation of alternative/ complementary therapies.
Summary
"There are no clinical data to support the use of this herb for any medical condition. Besides lapachol and xyloidone, other chemical component of pau d'arco have not been studied. Because hydroquinone compounds are known to possess toxic effects, pau d'arco should be considered potentially toxic. Therefore, its use cannot be recommended." (Fetrow)
"Its lack of proven effectiveness, its potential toxicity, and its relatively high cost render its use both unwise and extravagant." (Tyler)
Description/ Source/ Components
"Pau d'arco products are made from the bark of Tabebuia impetiginosa (also known as T. avellanedai or Tecoma curialis). These evergreen flowering trees belong to the Bignonia family (Bignoniaceae) and are native to Florida, the West Indies, Mexico, Central America, and South America." (Fetrow)
"Approximately 15 quinone compounds have been found in the heartwood of Tabebuia impetiginosa, including lapachol, B-lapachone (both naphthoquinones), and tebebuin (an anthroquinone)." (Fetrow)
Pau d'arco is available as capsules (460 mg [milligrams]), tablets, skin salve, extracts, and teas. (Fetrow)
"The tea is prepared from leaves of various species of Tabebuia, a genus of about 100 broad-leaved, mostly evergreen trees found in the West Indies and in Central and South America." (Wilson)
The active compound is lapachol. (Power) Lapachol is a yellow crystalline material and is also known as lapachic acid, taiguic acid, tecomin and greenhartin. (Merck)
History
"The drug is claimed to have been popular in the old Inca Empire, long before the Spanish invaded the New World." (Tyler)
"Used by the Inca Indians of South America 1,000 years ago... still used by the Callawaya tribe, descendants of the Inca medicine men, to cure cancer and a host of other diseases." (Borino)
Proponent/ Advocate Claims
Proponents claim that pau d'arco "has anti-microbial properties that act as strengthening and cleansing agents." (Ontario)
"Taheebo has been used, with great success, to cure leukemia by medical doctors in Argentina. Taheebo is also used to treat anemia, arteriosclerosis, asthma, bronchitis, colitis, diabetes, skin sores, gastritis and a variety of infections." (Borino)
"The main active ingredient is a substance called lapachol, a substance whose molecular composition makes it uniquely suited to induce strong biological activity against cancer. Nine patients with various cancers (liver, kidney, breast and prostate adenocarcinomas, and squamous cell carcinoma of the palate and uterine cervix) were given pure lapachol in 250-mg [milligrams] capsules with meals. All 9 patients showed a shrinkage of tumors and reductions in tumor-related pain; 3 patients experienced complete remissions, and there were no adverse side effects. (Santana)" (Diamond)
Professional Evaluation/ Critique
In clinical trials, 19 patients with advanced nonleukemic tumors and 2 patients with chronic myelocytic leukemia in relapse were given lapachol in doses ranging from 250 to 3750 mg/day for 5 days. The largest total dose received was 3000 mg/day for 21 days. All patients had previously received a variety of therapies, which had failed. One patient with metastatic breast cancer had resolution of a single osteoblastic hip lesion, but no change in numerous other bony lesions; all other patients either remained clinically unchanged in condition or experienced advancing disease. (Block)
In February 1985, Taheebo was "banned by the (Canadian) Federal Health Protection Branch until distributors prove it is safe and effective... The Federal Food and Drug Act does not allow Taheebo to be advertised or sold as a treatment, prevention or cure for certain diseases, including cancer." (Power)
Cassileth lists pau d'arco tea for cancer and AIDS under the heading: "Products promoted as cures for illnesses they do not cure". (Cassileth)
"An analysis of 12 taheebo products available in Canada revealed that only one contained lapachol (Awang)." (Fetrow)
"Analysis of the barks of three Tabebuia species showed that, unlike the wood, they did not contain lapachol and dehydro-alpha-labachone as their major naphthoquinone constituents. Depending on the species, these compounds were either present in traces or entirely absent. Three lapachol derivatives were instead detected; their physiological properties appear to be very similar to those of lapachol. (Girard)" (Tyler)
"Complicating the matter of origin even further is the fact that some pau d'arco herbal teas marketed in this country do not derive from the Tabebuia species at all, even though they are labeled as lapacho colorado or lapacho marado. Instead, they are stated to represent the bark of Tecoma curialis Solhanha da Gama, another closely related member of the same plant family. This probably makes little difference because the useful constituents and therapeutic activities, if any, are undoubtedly similar. It nevertheless leaves the botanical source of pau d'arco products unclear." (Tyler)
"Human clinical trials have been inconclusive regarding the use of lapachol as an anticancer agent (Block) (Awang)." (Fetrow)
"In trials with human cancer patients, however, as soon as effective plasma levels were attained, undesirable side effects were severe enough to require that the drug be stopped." (Tyler)
"Recent in vitro [in an artificial environment] studies showed antineoplastic activity, but this action was inhibited by vitamin K1 (Dinnen)." (Fetrow)
Toxicity/ Risks
Side effects include "moderate to severe nausea, vomiting, anemia, and tendency to bleed." (Tyler)
Toxicity observed in patients participating in the clinical trials included nausea and vomiting and reversible prolongation of prothrombin time at very high doses. Clinical studies were terminated because of the anticoagulant effect of the substance and because a plasma level of 30 mg/ml, considered critical, required doses associated with nausea, vomiting and anticoagulation. (Block)
"Lapachol is reported to be a potent inhibitor of respiratory processes, inhibits iodine utilization by cell-free sheep thyroid tissue, and depresses the ability of rat ovaries to respond to the follicle-stimulating hormone of pregnant mares' serum." (Morrison)
"The toxic effects of orally administered lapachol were studied in rodents, dogs, and monkeys... Death occurred in monkeys after six doses of 0.5 g/kg/day and after five doses of 1.0 g/kg/day. Signs of toxicosis in both dogs and monkeys included moderate to severe anemia, reticulocytosis, normoblastosis, pallor of mucous membranes, bilirubinuria, and proteinuria. Additionally, transient thrombocytosis and leukocytosis, and elevated serum alkaline phosphatase activity and prothrombin times occurred in dogs." (Morrison)
Costs
Each package of pau d'arco tea may cost anywhere from $12 to $50. (CA, 1993)
Pau d'arco costs approximately $5 for 24 tea bags or $10 for 50 capsules. (Ontario, 1994)
References
Awang DVC. Commercial taheebo lacks active ingredient. Can Pharm J 1998;5:323-26.
Block JB, et al. Early clinical studies with lapachol (NSC-11905). Cancer Chemother Rep 1974;4(4):27-28.
Borino B. 1,000-year-old Inca cancer cure works. Globe 1981 Sept 15;28(37).
CA (Anonymous). Questionable methods of cancer management 'nutritional' therapies. CA: a Cancer Journal for Clinicians 1993 Sept/Oct;43(5):309-319.
Cassileth BR. Alternative medicine handbook: the complete reference guide to alternative and complementary therapies. New York: W.W.Norton & Co., 1998:97.
Diamond WJ, et al. An alternative medicine definitive guide to cancer. Tiburon: Future Medicine Publishing, Inc., 1997:834.
Dinnen RD, Ebisuzaki K. The search for novel anticancer agents: a differentiation-based assay and analysis of a folklore product. Anticancer Res 1997;17:1027-33.
Girard M, et al. Journal of Natural Products 1988;51:1023-24.
Fetrow CW, Avila JR. Professional's handbook of complementary and alternative medicines. Springhouse, Pennsylvania: Springhouse Corporation 1999:491-93.
Merck Index: an encyclopedia of chemicals, drugs and biologicals. 10th ed. Rathway, N.J.: Merck 1983;772.
Morrison RK, et al. Oral toxicology studies with lapachol. Toxicol Appl Pharm 1970:17;1-11.
Ontario Breast Cancer Information Exchange Project. Guide to unconventional cancer therapies. 1st ed. Toronto: Ontario Breast Cancer Information Exchange Project, 1994:85-87.
Power B, Parton N. Cancer 'cure' sales banned. Sun 1985 Feb 14:1.
Santana CF, et al. Preliminary observations with the use of lapachol in human patients bearing malignant neoplasms. Revista da Instituto de Antibioticos 20 1980/81:61-68.
Tyler VE, Foster S. Tyler's honest herbal: a sensible guide to the use of herbs and related remedies 4th Ed. New York: Haworth herbal press, 1999:287-9.
Wilson BR (M.D.). Cancer quackery primer. Dallas, Oregon: The author, 1986.
Revised February 2000