Known interactions

2-Amino-2-Deoxyglucose, Abciximab Injection, Acanthopanax senticosus, Achillea, Achillea millefolium, Ackerkraut, African Pepper, Agathosma betulina, Aggrastat, Agrimonia, Agrimonia eupatoria, Agrimony, Agrylin, Alfalfa, Alhova, Allium, Allium sativum, Altamisa, Amachazuru, American Cranberry, Anagrelide, Angelica polymorpha, Angelica sinensis, Anthemis nobilis, Apricot Vine, Arandano, Ardeparin Sodium Injection--No longer available, Armoracia rusticana, Arnica, Arnica montana, Asian Ginseng, Aspirin and Carisoprodol, Aspirin, Caffeine and Dihydrocodeine, Awa, Barosma betulina, Basket Willow, Bee Bread, Bird Pepper, Bird's Foot, Black ginger, Bloodwort, Borage, Borago officinalis, Bridewort, Bucco, Buchu, Buffered Aspirin and Pravastatin, Bugloss, Buku, Cabbage Palm, Cacari, Caffeine, Aspirin and Dihydrocodeine, Camocamo, Camu-camu, Canton ginger, Capsicum, Capsicum annuum, Capsicum frutescens, Carica papaya, Carisoprodol Compound, Chamomile, Chili Pepper, Chinese Angelica, Chinese Ginseng, Chinese Sage, Chitosamine, Chondroitin, Chondroitin Sulfate, Chrysanthemum parthenium, Church Steeples, Ci Wu Jia, Cilostazol, Clopidogrel, Cochin ginger, Cochlearia armoracia, Cocklebur, Common Borage, Common Bugloss, Common ginger, Corona de Cristo, Coumadin, Coumadin Injection, Cow Clover, Crack Willow, Cranberry, Curcuma, Curcuma species, Daidzein, Dalteparin Injection, Danaparoid Injection, Danggui, Danshen, Devil's Bush, Devil's Claw, Devil's Leaf, Dihydrocodeine, Aspirin and Caffeine, Diosma, Dipyridamole, Dipyridamole Injection, Dong Quai, Dropwort, Eleuthero, Eleutherococcus senticosus, Enoxaparin Injection, Eptifibatide, Evening Primrose, Fan Palm, Featherfew, Fenugreek, Feuille de Luzerna, Fever Plant, Feverfew, Filipendula ulmaria, Flaxseed, Flaxseed oil, Flirtwort, Fragmin, Funffing, Gan Cao, Garden ginger, Garlic, Ge Gen, Genuine chamomile, German Chamomile, German Mustard, Gingembre, Ginger, Ginkgo, Ginkgo Biloba, Ginseng, Panax, Glucosamine, Glucosamine Hydrochloride, Glucosamine Sulfate, Glycine max, Glycine soja, Glycyrrhiza glabra, Goat's Pod, Graine de lin, Granadilla, Grape Seed, Grape Seed Extract, Grapple Plant, Great Raifort, Greek Clover, Greek Hay, Green Arrow, Guavaberry, Guigai, Gynostemma, Gynostemma pentaphyllum, Harpagophytum procumbens, Heparin Injection, Herbe de Saint-Guillaume, Horse Chestnut, Horse Radish, Horseradish, Hu Lu Ba, Huang Ken, Hungarian chamomile, Imber, Indian Saffron, Innohep, Integrilin, Jamaican ginger, Jantoven, Japanese Arrowroot, Japanese Ginseng, Japanese Silver Apricot, Jiaogulan, Kava, Kava-Kava, Kawa, Kew, Kew Tree, Korean Ginseng, Kudzu, Lady of the Meadow, Leinsamen, Leopard's Bane, Licorice, Linseed, Linseed oil, Lint bells, Linum, Liquorice, Liverwort, Lovenox, Lucerne, Maidenhair Tree, Matricaria chamomilla, Maypop, MEL, Meadow Clover, Meadowsweet, Medicago, Medicago sativa, Melatonin, Methi, Mexican Chillies, Milfoil, Miracle Grass, MLT, Mossberry, Mountain Radish, Mountain Snuff, Mountain Tobacco, Muscat, N-acetyl Glucosamine, N-acetyl-5-methoxytryptamine, Nettle, Nettle Tops, Ninjin, Normiflo - No longer available, Nosebleed Plant, OEP, Oenothera species, Orgaran, Oriental Ginseng, Ox's Tongue, Panax Ginseng, Panax schinseng, Papain, Paprika, Passiflora incarnata, Passion Flower, Passion Vine, Pepperrot, Persantine, Persantine Injection, Piper methysticum, Plavix, Pletal, Pravigard PAC, Pueraria, Pueraria lobata, Pueraria montana, Pueraria thunbergiana, Pulmonaria Officinalis, Purple Clover, Purple Medick, Pyrethrum parthenium, Queen of the Meadow, Radix Salvia, Red Clover, Red Cole, Red Ginseng, Red Pepper, Red Sage, Red Wine Extract, ReoPro, Roman Chamomile, Roman Nettle, Rumberry, Russian Root, Rustic Treacle, Sabal, Sabal serrulata, Salix, Salix alba, Salix fragilis, Salix purpurea, Salvia miltiorrhiza, Salvia Root, Saw Palmetto, Scrub Palm, Seng, Serenoa, Serenoa repens, Shigoka, Siberian Ginseng, Sodol Compound, Soma Compound, Southern Ginseng, Soy, Soya, Soybeans, Spirea, Spirea ulmaria, Starflower, Staunch Weed, Stickwort, Stinging Nettle, Stingnose, Stinking Rose, Sun Drop, Sweet Root, Synalgos-DC, Tabasco Pepper, Taiga, Tanacetum parthenium, Tang-Kuei, Ten Shen, Thorny Pepperbush, Thousand-Leaf, Ticlid, Ticlopidine, Tinzaparin, Tirofiban, Tonga, Touch-Me-Not, Trefoil, Trifolium pratense, Trigonella, Trigonella foenum-graecum, Turmeric, Urtica species, Vaccinium species, Vegetable pepsin, Vitis pentaphyllum, Vitis vinifera, Warfarin, Warfarin injection, Water Lemon, White Willow, Wild Chamomile, Wild Clover, Wild Pepper, Wild Quinine, Winterlein, Wolf's Bane, Wolfbane, Wood Spider, Wound Wort, Xianxao, Yagona, Yarrow, Yarroway, Yege, Yinhsing, Zanzibar Pepper, Zingiber officinale.

Quick guide to Taheebo

Scientific Name: Pau D'arco

Other Names: Ipe Roxo, Ipes, Lapacho, Tabebuia species, Taheebo, Trumpet Bush

Who is this for?

Due to case reports that pau d’arco had strong anticancer effects, several studies were undertaken by the U.S. National Cancer Institute and other organizations during the 1960s and 1970s. Generally, the results of laboratory, animal, and human studies showed that pau d’arco may prevent, delay, or treat cancer; but the oral doses needed to reach useful levels in the blood also cause severe side effects. Research for the anticancer effects of pau d’arco was discontinued in the United States, although such studies may continue in other parts of the world.

In the laboratory, chemicals derived from pau d’arco, have been studied for treating a number of conditions other than cancer. One chemical known as lapachol has been shown active against the parasite that causes malaria. Lapachol also seems to inhibit herpes simplex, the virus that causes cold sores. At low doses, chemicals in pau d’arco may help to activate the immune system; but higher doses appear to have an immune-weakening effect. Currently, more effective oral medicines with fewer side effects are available to treat malaria and cold sores, but lapachol and other chemicals in pau d’arco may be active against other parasites and viruses. Much more study is needed for their potential oral use. At this time, therefore, oral pau d’arco is not recommended for treating any medical condition.

Topically, pau d’arco appears to have varying amounts of antibacterial, antifungal, antiprotozoal, and antiviral properties. It may be anti-inflammatory, as well; but none of these potential topical uses have been well-studied. In South America, pau d’arco is used topically to treat insect or snake bites, minor skin injuries, and more serious conditions such as psoriasis.

When should I be careful taking it?

In animal studies, a high number of birth defects and deaths occurred among developing animals whose mothers were given pau d’arco during pregnancy. Although no reports of similar effects have been reported in humans, pregnant women are advised to avoid taking pau d’arco by mouth.

Because pau d’arco may decrease the blood’s ability to clot, it should not be used by individuals who have bleeding disorders such as hemophilia.


Not enough is known about how pau d’arco might affect an infant to recommend its use while breast-feeding. In addition, it should not be given to small children.

What side effects should I watch for?

Taking pau d’arco may cause anemia, a reduction in the number of red blood cells produced by the body. Symptoms of anemia may include

  • Fatigue
  • Pale, cool skin
  • Shortness of breath
  • Skipped heartbeats

Less Severe Side Effects

In human studies, pau d’arco also caused a number of side effects that appeared to worsen as the dose of pau d’arco increased. Among these side effects were:

  • Diarrhea
  • Dizziness
  • Nausea
  • Vomiting

What interactions should I watch for?

Prescription Drugs

In studies and case reports, pau d'arco has been shown to increase the time blood needs to clot. When it is taken with antiplatelet or anticoagulant drugs, the effect of the drug may be increased, resulting in uncontrolled bleeding.

  • Antiplatelets include Plavix and Ticlid
  • Anticoagulants include heparin and warfarin

Non-prescription Drugs

Orally, pau d'arco may decrease the ability of blood to clot after an injury. Aspirin can also delay clotting, so pau d'arco should not be taken orally at the same time as aspirin.

Herbal Products

Theoretically, if pau d'arco is used with other herbs that affect blood clotting, bleeding may occur. Some of the most common herbal products that might inhibit blood clotting are:

  • Danshen
  • Devil's Claw
  • Eleuthero
  • Garlic
  • Ginger (in high amounts)
  • Ginkgo
  • Horse Chestnut
  • Panax Ginseng
  • Papain
  • Red Clover
  • Saw Palmetto

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals.

Should I take it?

Pau d’arco is a broad-leaf evergreen tree native to the rainforests of Argentina, Brazil, and Paraguay. It is also found in other tropical areas of South America, Central America, the Caribbean Islands, and Africa. Pau d’arco trees are very large – reaching 100 to 150 feet in height and often towering over other rainforest vegetation. They are particularly attractive in the spring, when they are covered in thick clusters of trumpet-shaped flowers that usually range from pink to bright red in color.

Because it is especially hard and durable, the wood of pau d’arco has been used to make boats and farming implements, as well as buildings. Some native people used it to make bows and arrows – in fact, the name “pau d’arco” means “bow stick” in Spanish. For medicine, the “inner” bark (the light-colored, spongy layer between the rough “outer” bark and the heartwood of the tree) is used. After the light brown inner bark is separated from the darker outer bark, the inner bark is dried and then shredded or powdered. Unfortunately, removing too much of the inner bark will kill the tree, so some native populations of pau d’arco trees are in danger of becoming extinct.

Dosage and Administration

Several different types of pau d’arco trees grow in various parts of the world. The inner layer of bark is the part used in medicine. The amounts of active chemicals in pau d’arco products cannot be guaranteed because they depend on the type of tree as well as on how bark is harvested, processed, and stored. In addition, outer bark, wood, or other parts of pau d'arco or other trees may be mixed with pau d'arco's inner bark.

In general, however, pau d’arco contains up to 7% of lapachol. In human studies, doses of pau d’arco that provided over 1,500 mg (1.5 grams) per day of lapachol were associated with severe side effects that include anemia, increased risk of uncontrolled bleeding, and severe nausea and vomiting. Due to the probability of these serious side effects, taking pau d’arco orally cannot be recommended.

In some countries of South and Central America, pau d’arco tea is common. Because the medically-active chemicals in pau d’arco do not dissolve very well in water, however, soaking the inner bark of pau d’arco in hot water does not usually produce a tea with much medical activity. Boiling the inner bark or wood of pau d’arco for at least 10 minutes and then cooling and straining out the solid particles may produce a mildly effective topical solution. This liquid may be used as a skin wash or poultice for conditions such as psoriasis.


The potentially serious side effects caused by dose levels necessary to produce medical effects make oral pau d’arco too risky to recommend for use in any medical condition. Topical solutions of pau d’arco may be mildly anti-infective and they may be used to relieve skin conditions.


While all individuals are advised not to take pau d’arco, its oral use should be avoided especially by individuals with bleeding disorders, by pregnant or breast-feeding women, and by small children.

Side Effects

Due to its possible anticoagulant properties, pau d’arco may cause anemia and it may increase the risk of uncontrolled bleeding. Taking pau d’arco has also been associated with dizziness, nausea, and vomiting – which may become more severe as the dose increases.


Pau d’arco may increase the anticoagulant effects of drugs and herbals that limit the blood’s ability to clot.


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(Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.)

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