What Is Pau D'Arco?

Can this Amazonian tree bark fight infection and inflammation?

Pau d'arco capsules, tablets, tincture, and tea bags

Verywell / Anastasia Tretiak

Pau d'arco comes from tree bark of the Tabebuia impetiginosa or Tabebuia avellanedae species. It contains plant-based naphthoquinone compounds called lapachol and beta-lapachone. Vitamin K is also a naphthoquinone and increases blood clotting. This may explain why pau d'arco may sometimes cause the side effect of impaired blood clotting.

These plant-based compounds, drawn from the rainforests of Central and South America, are studied for their potential antibacterial, antiviral, and antifungal effects. Pau d'arco has been an ingredient in herbal medicines for centuries and is available as a dietary supplement. It also includes a potent antioxidant known as quercetin. Research has investigated the individual components of pau d'arco and the whole plant. The use of the whole plant sometimes results in a synergistic effect. This means the whole plant might work better than just one of its chemical components alone.

This article looks at the current research on pau d'arco. This research includes preliminary studies that could lead to treatment for those living with inflammatory illnesses (like arthritis) and infections caused by a yeast called Candida. This article also lists common dosages and the possible side effects and risks associated with this herbal remedy.


Everything You Need to Know About Pau D'Arco

Dietary supplements are not regulated like drugs are in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before the companies that produce them market them. When possible, choose a supplement that a trusted third party, such as USP, ConsumerLab, or NSF, has tested.

However, even if supplements are third-party tested, that doesn’t mean they are necessarily safe for all or effective in general. Therefore, it is important to talk to your healthcare provider about any supplements you plan to take and to check in about any potential interactions with other supplements or medications.

Supplement Facts

Active ingredients: Beta-lapachone, lapachol, quercetin.

Alternate names: Bow tree, ipe, lapacho, Tabebuia impetiginosa, Tabebuia avellanedae, Tabebuia, taheebo

Legal status: Over-the-counter herbal supplement (United States)

Suggested dose: No suggested dosage guideline is available.

Safety considerations: Bleeding or clotting problems (avoid pau d’arco).

Uses of Pau D'Arco

A healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider, should individualize and vet supplement use. No supplement's purpose is to treat, cure, or prevent disease.

Folk medicine has often put pau d'arco forth as a treatment for a wide range of medical disorders, including anemia, asthma, bronchitis, diabetes, eczema, enlarged prostate, influenza, intestinal worms, sexually transmitted infections, skin infections, urinary tract infections, and cancer. However, there is generally no quality evidence supporting any of this. 

There is some preliminary evidence from research in animals, animal cells, and human cells that pau d'arco could one day help treat medical conditions. The term for research conducted on cells is in vitro research. This phrase lets you know that studies of pau d'arco in human use are insufficient to draw conclusions yet.

Here is a look at some of these critical research findings.


Pau d'arco has been studied in several types of inflammation, including Pau d'arco (Tabebuia avellanedae) extract decreasing inflammatory cyclooxygenase II (COX-2) in human cells.

Researchers studied pau d'arco (Tabebuia avellanedae) water extract in mouse cells and live mice. The mouse cell study showed decreased production of some inflammatory chemicals, including prostaglandins, nitric oxide, and COX-2. These results suggest pau d'arco may have some anti-inflammatory effects. In the live mouse study, researchers gave the animals a substance called arachidonic acid to cause ear swelling. They found that the Tabebuia avellanedae extract given to the mice by mouth decreased the swelling.

More about prostaglandins: Prostaglandins appear at tissue damage or infection sites. They cause inflammation, pain, and fever as part of the healing process. By countering this effect, pau d'arco may reverse the swelling and pain associated with inflammatory conditions such as osteoarthritis, rheumatoid arthritis, and benign prostatic hyperplasia (enlarged prostate). These effects are still theoretical, and more study in people is necessary before researchers can draw firm conclusions.

Another study also gave Tabebuia avellanedae water extract to mice who had colitis to test its anti-inflammatory effects. Scientists found that the extract caused mice to have fewer clinical symptoms and reduced tissue inflammation. Like the previous study, results from mouse studies are somewhat promising but do not necessarily apply to humans.


The Tabebuia tree's bark is highly resistant to rotting, mold, and other common tree pathogens (bacteria, viruses, or other tiny organisms that may cause disease). These properties may or may not eventually translate to the treatment or prevention of common bacterial, viral, or fungal infections in people. This section includes one study in humans that used a combination product, but most research involved animals and in vitro study instead.

Fungal infections

Scientists conducted a small study in 60 people with vaginal yeast infections caused by Candida. The people received a combination treatment product that contained several compounds, including Tabebuia and hydroxytyrosol. During three months of treatment, 49 people reported no Candida episodes. This is promising but may not apply to people who take Tabebuia alone.

An early in vitro study of plant extracts, including Tabebuia extract, also tested their activity against Candida albicans. Tabebuia extract showed inhibition of some fungus strains that cause human disease. These included strains of Candida, Aspergillus, Saccharomyces, and Penicillium.

Viral and parasitic Infections

A review suggested that Tabebuia impetiginosa may have antiviral effects against the human herpes virus and that a compound derived from lapachol may have antiparasitic effects in vitro.

Bacterial infections

An in vitro study tested the antimicrobial effects of lapachol, a compound in pau d’arco. The bacteria tested included ones that could cause severe human infections, such as Enterococcus faecalis, Staphylococcus aureus, Cryptococcus gattii, and Paracoccidioides brasiliensis. Lapachol showed activity against all these microorganisms.

Another in vitro study looked at whether plant medicines like pau d’arco could work along with some antibiotics to make them more effective. This study tested a combination of Tabebuia avellanedae bark extract and other medicinal plants against bacteria, including Haemophilus influenzae, Staphylococcus aureus, and Klebsiella pneumoniae. Scientists also tested the antibacterial effects of combining medicinal plants with antibiotics. These included clarithromycin, azithromycin, and amoxicillin/clavulanic acid. Results showed that the medicinal plant extracts sometimes increased antibacterial activity, which is a path for future study. 

Despite the promising results of these studies, the dosages used in many in vitro experiments would be toxic in humans. Further investigation in humans is necessary before researchers can draw any firm conclusions.

Wound Healing

Researchers studied the wound-healing effects of beta-lapachone, a component of pau d’arco.

Scientists tested the effects of beta-lapachone on mouse cells, human cells, and live mice. Beta-lapachone caused cells to release proteins involved in wound healing. Beta-lapachone ointment used in mice also led to faster recovery than ointment without the added beta-lapachone.

Researchers cannot apply these results to humans like the other animal and in vitro studies in this article. They only mean that further research is worthwhile.


Compounds in pau d'arco have shown in vitro evidence for inhibition of the growth of some types of tumors. This is not the same as effectiveness against cancer in a person.

Check with your healthcare provider before adding integrative treatments to your cancer treatment regimen. Sometimes medicinal herbs can worsen your symptoms or even interact with your cancer medicine. Remember, avoid replacing your cancer treatment with herbal medicine. 

Here are some of the research findings.

In a review of studies about Tabebuia impetiginosa, scientists concluded that the beta-lapachone found in pau d'arco was able to trigger apoptosis (programmed cell death) in certain types of cancer cells.

Another in vitro study that treated breast cancer cells with powder from the inner bark of the Tabebuia avellanedae tree met with similar results. Scientists reported that breast cancer cells showed increased apoptosis and stopped an enzyme involved in breast cancer called aromatase.

More about apoptosis: All normal cells undergo apoptosis so new cells can replace old cells. Cancer cells, however, are "immortal," replicating without end. Triggering apoptosis (cell death) can theoretically control cancerous tumors.

Although there is promising evidence from cells and test tubes for future cancer drug discovery, pau d'arco does not yet have evidence for treating or preventing cancer.

What Are the Side Effects of Pau d'Arco?

Little is known about the long-term safety of pau d'arco. However, it does have some side effects of which you need to be aware.

Common Side Effects

Common side effects include dizziness, nausea, vomiting, and diarrhea. The risk and severity of side effects tend to increase with the dose.

Severe Side Effects

Severe allergic reaction is another serious side effect that is possible with any medication. If you're having a severe allergic reaction to pau d'arco, get medical help immediately. Symptoms may include but aren't limited to:

  • Difficulty breathing
  • Itchiness
  • Rash

To avoid interactions or potentially severe side effects, always consult your healthcare provider about any herbal supplement or medication you take. And call 911 if your symptoms feel life-threatening.


Pau d'arco may slow blood clotting because it inhibits blood clotting factors that depend on vitamin K.

You should stop taking any medicine or herb that inhibits clotting or increases the risk of bleeding for at least two weeks before surgery. Ask your healthcare provider if you also need to stop taking any of your medications or supplements temporarily if you have surgery planned.

Due to the lack of safety research, children or people who are pregnant or breastfeeding should not take pau d'arco. Limited animal studies showed fetal harm with lapachol.

People with kidney or liver disease should also take it with caution.

Pau d'arco tablets

Verywell / Anastasia Tretiak

Dosage: How Much Pau d'Arco Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs. 

Pau d'arco is available as capsules, tablets, dried bark tea, bark powder, and alcohol-based tinctures. There are no guidelines directing its appropriate use.

Doses that have been researched include 250 milligrams (mg) to 3,750 mg daily. Dosages on various supplement labels include 2.5 milliliters (mL) or 1 mL tincture mixed with water and 1 gram (g) or 500 milligrams (mg) in a capsule.

Accurately calculating the dosage of pau d'arco in tea form is sometimes difficult.

What Happens if I Take Too Much Pau D'Arco?

Information about the toxicity of pau d'arco in humans is sparse.

However, a study in male rats taking high levels of Tabebuia impetiginosa extract showed damage to DNA in liver cells. This effect was dose-dependent, meaning the damage increased as the dose increased.

The exact translation of this information for humans is unclear. However, people with kidney or liver disease should take it cautiously.


Because pau d'arco can slow blood clotting, it can cause a negative interaction with blood thinners like Jantoven (warfarin) or Plavix (clopidogrel).

Non-steroidal anti-inflammatory drugs (NSAIDs) have a theoretical interaction with pau d’arco. Although there are no published studies about pau d’arco interacting with NSAIDs, this can still happen. Any supplement that affects bleeding can increase the risk of bleeding that is already present as a side effect of NSAID use.

Whatever pau d'arco product you buy, read the label carefully to ensure that it contains Tabebuia avellanedae or Tabebuia impetiginosa as an ingredient.

Carefully reading a supplement's ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient it includes is essential. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications. 

How to Store Pau d'Arco

Store pau d’arco in a cool, dry place. Keep pau d’arco away from direct sunlight. Discard as indicated on the packaging.

Similar Supplements

Pau d’arco is available as a whole plant extract or bark, but it also contains quercetin, which companies often sell as a separate supplement.

Frequently Asked Questions

  • Can pau darco treat cancer?

    Despite suggestions that pau d'arco may work to fight breast cancer and prostate cancer cells, there is no evidence of any such effect in humans. The research has remained limited to test-tube studies and a few small animal studies.

  • Is the pau d'arco tree endangered?

    The popularity of pau d'arco in traditional medicine has led to concerns about its sustainability. As a canopy tree of the Amazon, it is one of many species facing extinction as deforestation continues to wreak havoc on the rainforests of Brazil. Related Tabebuia species are on the vulnerable or threatened species list. Learn more about ways to be eco-conscious in your everyday life.

  • Is pau d'arco an anti-inflammatory tea?

    We don’t know yet. Although researchers have studied pau d’arco in animals and test tubes for anti-inflammatory effects, there is no evidence for this use in people yet. They have studied teas with health benefits and foods with anti-inflammatory effects more than they have pau d’arco. Most importantly, consuming a diet high in vegetables and fruit, fiber, enough protein, and whole grains can support your overall health.

Sources of Pau d'Arco and What to Look For

Pau d’arco supplements are available in drug stores and online. Although you may find it difficult to make sure that you will always get the exact amount of pau d’arco on its packaging's label, you can choose brands that are more reputable. Ask your healthcare provider for recommendations of brands that are known to have undergone testing for impurities. 

Pau D'Arco Supplements

The forms that pau d'arco comes in include:

  • Capsules
  • Tinctures
  • Teas 

If you choose the tea form, you may have some difficulty estimating the dosage you are taking.

To ensure quality and safety, opt for supplements independently tested by a certifying body like the U.S. Pharmacopeia (USP), National Science Foundation (NSF), or ConsumerLab. These certifications confirm that the supplement contains the ingredients and ingredient amounts listed on the product label.

Always read the label to check for any added ingredients you may have allergies or sensitivities to, including gluten and animal-based gelatins.

Talk with your healthcare provider first if you're considering using pau d'arco or making other dietary changes. Self-treating a condition and avoiding or delaying standard care may have serious consequences.


Pau d'arco is the bark of several species of trees native to the rainforests of Central and South America. It has long been part of folk medicine.

Research on pau d'arco has mostly been in vitro and for animals. There have been promising results that it may have future potential for treating some types of infections, inflammatory conditions, and cancers. This evidence does not support the use of pau d'arco to treat any conditions in humans yet.

Due to the lack of safety research, children, people who are pregnant or breastfeeding, or people with liver or kidney problems should not use pau d'arco. You should also avoid it if you take blood thinners or non-steroidal anti-inflammatory drugs, or if you have any medical conditions affecting bleeding or clotting.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Carla Eisenstein, PharmD
Carla Eisenstein is a pharmacist and medical writer passionate about clear communication in science and medicine. She has experience in drug information, medical communication, social media, and patient advocacy.

Originally written by Cathy Wong
Cathy Wong

Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.

Learn about our editorial process