Pau d’arco is the name for some species of Tabebuia trees and a dietary supplement made from their inner bark. Limited research on its application and safety suggests it may have anti-inflammatory, antimicrobial, and anticancer properties.
Also known as taheebo or lapacho, pau d’arco has been used by many cultures as a natural treatment for a range of ailments. As a supplement in the United States, it’s marketed to reduce inflammation and promote weight loss.
Pau d’arco: Origin, uses, and potential health benefits
Pau d’arco is the common name for several species of Tabebuia trees native to South and Central America’s tropical rainforests. These trees can grow up to 125 feet tall and usually have pink-to-purple flowers.
But it’s pau d’arco’s inner bark that gets the most attention. Central and South American native tribes have long used it as a treatment for stomach, skin, and inflammatory conditions. However, research on these potential benefits is limited.
Pau d’arco has several compounds that may have clinical applications, including:
- naphthoquinones — mainly lapachol and its derivative beta-lapachone
- quercetin
- flavonoids
- phenolic acids
- fatty acids
Existing research on pau d’arco and its components has limitations, including the fact that most studies are in vitro, which may not accurately represent potential effects in the human body.
Other challenges include significant differences in methodology between studies and used compound concentration levels.
What the research on pau d’arco and its components says
Although dietary pau d’arco supplements are often marketed as weight loss aids, there’s no research to back up these claims.
Additionally, supplements in the United States are not regulated or monitored for safety and effectiveness as pharmaceutical products are, so caution is advised when using these products.
Preliminary research on the compounds found in pau d’arco has suggested that they may have anti-inflammatory, anticancer, antimicrobial, and other protective properties.
For example, a 2023 study on the effects of beta-lapachone on colorectal cancer cells that do not respond to chemotherapy indicated that the compound inhibited the growth of these cells. It also lowered levels of specific proteins associated with cancer cell multiplication and survival.
Researchers could not explain the mechanisms of action behind this process, though. The study was done in vitro, which means the results may not necessarily apply to the human body.
A 2021 comprehensive review found that beta-lapachone may have potential anticancer, antimicrobial, neuroprotective, and cardiovascular therapeutic properties. Researchers noted that beta-lapachone inhibits tumor growth and suppresses metastasis in cancer cells in in vitro and animal model studies. When used in combination, beta-lapachone may also enhance other anticancer agents.
The same review found that beta-lapachone is effective at fighting bacteria and fungi, which may be helpful in the management of some infectious diseases. It may also protect brain cells, reduce oxidative stress, and lower inflammation, which holds potential for the management of conditions like heart disease, dementia, and Parkinson’s disease.
Additionally, a 2020 research review indicated that beta-lapachone has repeatedly shown anti-inflammatory properties in animal and in vitro studies, which researchers say may hold promise for the management of inflammatory conditions like arthritis, asthma, and inflammatory bowel disease (IBD).
A 2020 laboratory study also found that alpha-lapachone and beta-lapachone play an important role in wound healing. Researchers noticed that both compounds speed up cell migration, which helps tissue regenerate itself faster. The compounds also stimulate the production of proteins that facilitate the wound-healing process.
Quercetin seems to be another important pau d’arco component. A 2023 research review of the research done on the potential health benefits of quercetin indicated that this compound may:
- reduce inflammation
- protect cells from free radicals (antioxidant effect)
- boost immunity
- lower blood pressure
- reduce cholesterol levels
- inhibit the growth of cancer cells
Although the research on compounds of pau d’arco seems promising, it’s important to note that most studies have been conducted in a laboratory setting and do not account for the complexities of the human body or individual variations.
There’s also very limited research on the safety and side effect considerations of these compounds, including on pau d’arco supplements or products specifically.
Potential risks and side effects of pau d’arco
The lack of clinical trials and research on humans means pau d’arco products should be used with caution and under medical supervision to avoid adverse effects like:
- interaction with medications
- toxicity
- internal organ damage
- overdose
Pau d’arco is possibly unsafe, particularly in high doses, if taken by mouth. Possible side effects may include:
- severe nausea
- severe diarrhea
- severe vomiting
- dizziness
- internal bleeding
Pau d’arco may interfere with clotting so people with clotting disorders or who will have surgery shouldn’t take these products. Pregnant and nursing people are also advised to avoid pau d’arco products.
The bottom line
The existing research on the potential benefits of pau d’arco and its compounds is limited and focused on laboratory and animal model studies.
This, paired with the fact that supplements in the United States do not undergo strict safety and effectiveness regulations, means that consulting with a healthcare professional is highly advised before using any pau d’arco products.