Herb & supplement monograph

Chaparral Drug Interactions, Uses, Safety & More

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS ·Updated July 2026

What is this page for?

First and foremost: how Chaparral interacts with medications. The heart of this page is the interaction list — every drug Chaparral is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Chaparral is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

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Chaparral Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, the overall risk of a clinically significant Chaparral drug interaction appears low for most people, though every concern in the data points to one organ: the liver. None of the listed interactions are rated major, and all of them rest on the same theoretical worry rather than documented harm in humans.

Interactions deserving the most attention

The interactions that deserve attention all involve medications that can strain the liver, sometimes called hepatotoxic drugs. The concern is that chaparral might add to the stress these medicines already place on the liver, making side effects there more likely. That said, this is graded as only possible, meaning it comes from lab or animal research or limited reports, not from well-controlled human studies. If a medicine you take carries its own liver warnings, this combination is the one worth discussing.

What the rest of the list means

Although the list of interacting medications is long, it reflects a single shared theme rather than hundreds of separate problems. Any medicine with known liver effects was flagged as a precaution. So far, this additive liver effect remains a prediction, and it has not been confirmed to cause meaningful harm in people.

Check your medications against Chaparral

Based on HelloPharmacist’s Chaparral interaction data and reviewed under our editorial standards.

Interaction report

Drugs that interact with Chaparral

372 medications have a known interaction with Chaparral, graded by severity. Select any drug for the full evidence-based detail.

Don’t want to scroll the list? Just ask.

Tell us the medications you take and we’ll check each one against Chaparral using our pharmacist-reviewed interaction data.

AI summaries are generated from our Chaparral interaction data for education only — always confirm with your pharmacist. How we use AI

2,830 drugs

Read The List Like a Pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
Each drug listed above links to the full report for that exact Chaparral combination — clinical detail, likelihood, evidence level, and citations.
Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

The big picture

The kinds of drugs Chaparral affects

Every type of medication (drug category) Chaparral is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 1 drug category Chaparral interacts with

Hepatotoxic Drugs

Theoretically, chaparral might have additive adverse effects on the liver when used with hepatotoxic drugs.

Likelihood Possible Evidence D

Monograph

Chaparral: Uses, Safety & Side Effects

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Reviewed July 2026 ·

The bottom line

Chaparral is a desert shrub long used in traditional medicine, but there is no reliable proof it treats any condition. It has been linked to serious and sometimes irreversible liver and kidney damage, and the FDA has warned against using it. Because of these safety concerns, we recommend avoiding chaparral.

Scientific name: Larrea tridentata
Family: Zygophyllaceae
Part used: Leaves and twigs
Common forms: Tea, capsules, tablets, tinctures, topical salves

People commonly use it for

Pain and inflammation
Skin conditions
Antioxidant/general wellness
Infections
Traditional 'detox' remedies

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance

OverallBest avoided

Chaparral has been linked to serious liver and kidney toxicity and is not recommended.

PregnancyLikely Unsafe

When used orally. There are several reports of serious poisoning, acute hepatitis, and kidney and liver damage, including irreversible renal and hepat...

Read the full pregnancy detail

BreastfeedingLikely Unsafe

When used orally. There are several reports of serious poisoning, acute hepatitis, and kidney and liver damage, including irreversible renal and hepat...

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

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Overview

Chaparral, also called creosote bush, comes from a flowering shrub (Larrea tridentata) that grows in the dry deserts of the southwestern United States and northern Mexico. It has small yellow flowers and a strong smell, especially after rain.

For many years, Native American and traditional healers used chaparral leaves and twigs as a tea or a topical remedy. Today it is sometimes sold as a dietary supplement in capsules, teas, tinctures, and skin salves, often marketed for pain, inflammation, or so-called 'detox' purposes.

Because of reports of serious liver and kidney harm, the U.S. FDA has advised people not to take chaparral products.

Uses & effectiveness

People have traditionally used chaparral for a wide range of problems, including pain, arthritis, inflammation, skin conditions, infections, and as a general 'tonic' or 'detox.' Some marketers have also promoted it for serious diseases such as cancer.

There is no good scientific evidence that chaparral safely treats any of these conditions. Most claims come from laboratory studies, animal research, or traditional use rather than well-designed human trials. Claims that it can cure cancer or other serious illnesses are not supported by reliable evidence.

Given the lack of proven benefit and the real risk of harm, the potential dangers of chaparral outweigh any possible value.

How it works

Chaparral contains a compound called nordihydroguaiaretic acid (NDGA), along with other plant chemicals. NDGA is an antioxidant in laboratory tests and can affect certain enzymes in the body.

In test-tube and animal studies, these compounds have shown antioxidant and anti-inflammatory activity. However, these same effects on the body's chemistry are also thought to play a role in chaparral's toxicity, especially to the liver.

It is important to know that effects seen in a lab dish or in animals do not mean the herb works safely in people.

Safety & precautions

Chaparral can cause serious harm. It has been linked to cases of liver toxicity, including hepatitis and liver failure, with some people needing a liver transplant. It has also been associated with kidney problems. Some of this damage can be permanent.

Because of these reports, the FDA issued a warning against using chaparral, and many products were pulled from the market. People with any liver or kidney disease should especially avoid it, but the risk applies to healthy people too.

Pregnancy and breastfeeding: Avoid chaparral if you are pregnant or breastfeeding. There is no safety data, and the risk of toxicity makes it especially dangerous during these times. Children should not use it either.

Always talk to a pharmacist or doctor before taking any herbal product, and be cautious of products that promise to cure serious diseases.

Side effects

The most serious concern is liver damage, which can show up as yellowing of the skin or eyes (jaundice), dark urine, nausea, vomiting, loss of appetite, abdominal pain, fatigue, or itching. Kidney problems have also been reported.

If you take chaparral and notice any of these symptoms, stop using it and seek medical care right away. Milder digestive upset is also possible. Because organ damage can occur without obvious early warning signs, the safest choice is to avoid the product entirely.

Chaparral: Reported Adverse Effects

Documented safety reports on Chaparral from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

Chaparral is generally regarded as unsafe for use. Any benefits of therapy may not outweigh the risk of toxicity. Orally, chaparral can cause hepatoxicity, resulting in jaundice, fatigue, right upper quadrant abdominal pain, dark urine, light stools, nausea, diarrhea, weight loss, fever, and anorexia. It can also cause cirrhosis, cholestasis, cholangitis, acute hepatitis, and liver failure possibly necessitating liver transplant. Consumption of chaparral tea has been associated with cystic renal disease and cystic adenocarcinoma of the kidney. Although some information suggests that low doses of chaparral can be used safely, a safe dose has not been established.

Topically, chaparral can cause contact dermatitis.

Reports by condition

Anorexia Hepatic

Orally, chaparral can cause hepatoxicity, resulting in jaundice, fatigue, right upper quadrant abdominal pain, dark urine, light stools, nausea, diarrhea, weight loss, fever, and anorexia. It can also cause cirrhosis, cholestasis, cholangitis, acute hepatitis, and liver failure Multiple cases of severe hepatotoxicity have been reported, including at least two cases requiring liver transplant.

The nordihydroguaiaretic acid (NDGA) constituent of chaparral is thought to be responsible for its hepatotoxic effect; however, the exact mechanism of toxicity is unknown. Although some information suggests that low doses of chaparral can be used safely, a safe dose has not been established.

Dermatitis Immunologic

Topically, chaparral can cause contact dermatitis.

Kidney failure Renal

Orally, chaparral can cause kidney failure. Consumption of chaparral tea has been associated with cystic renal disease and cystic adenocarcinoma of the kidney. In one case report, consumption of 3-4 cups of chaparral tea daily was associated with these symptoms .

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

Dosing

There is no safe or established dose for chaparral. Because it has been linked to serious liver and kidney damage, health authorities recommend not using it at all rather than trying to find a 'safe' amount.

If you are considering any herbal supplement, talk with a pharmacist or doctor first. For chaparral specifically, the best advice is to avoid it.

Pregnancy & Breastfeeding

Chaparral & Pregnancy

Likely Unsafe

When used orally. There are several reports of serious poisoning, acute hepatitis, and kidney and liver damage, including irreversible renal and hepatic failure. Advise patients not to use products containing chaparral.

Chaparral & Breastfeeding

Likely Unsafe

Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center

References & further reading

The 16 references that drive our Chaparral monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

Smith BC, Desmond PV. Acute hepatitis induced by ingestion of the herbal medication chaparral. Aust N Z J Med 1993;23:526.. PubMed
Gordon DW, Rosenthal G, Hart J, et al. Chaparral ingestion: the broadening spectrum of liver injury caused by herbal medications. JAMA 1995;273:489-90.
Batchelor WB, Heathcote J, Wanless IR. Chaparral-induced hepatic injury. Am J Gastroenterol 1995;90:831-3.
Katz M, Saibil F. Herbal hepatitis: subacute hepatic necrosis secondary to chaparral leaf. J Clin Gastroenterol 1990;12:203-6.
Klepser TB, Klepser ME. Unsafe and potentially safe herbal therapies. Am J Health Syst Pharm 1999;56:125-38. PubMed
Sheikh NM, Philen RM, Love LA. Chaparral-associated hepatotoxicity. Arch Intern Med 1997;157:913-9. DOI
Heron S, Yarnell E. The safety of low-dose Larrea tridentata (DC) Coville (creosote bush or chaparral): a retrospective clinical study. J Altern Complement Med 2001;7:175-85..
Chaparral-induced toxic hepatitis-California and Texas, 1992. MMWR Morb Mortal Wkly Rep 1992;41:812-4.. DOI
Estes JD, Stolpman D, Olyaei A, et al. High prevalence of potentially hepatotoxic herbal supplement use in patients with fulminant hepatic failure. Arch Surg 2003;138:852-8.. PubMed
Lambert JD, Zhao D, Meyers RO, et al. Nordihydroguaiaretic acid: hepatotoxicity and detoxification in the mouse. Toxicon 2002;40:1701-8.. PubMed
Shasky DR. Contact dermatitis from Larrea tridentata (creosote bush). J Am Acad Dermatol 1986;15:302.. PubMed
Smith AY, Feddersen RM, Gardner KD Jr, Davis CJ Jr. Cystic renal cell carcinoma and acquired renal cystic disease associated with consumption of chaparral tea: a case report. J Urol 1994;152:2089-91.. PubMed
Kauma, H., Koskela, R., Makisalo, H., Autio-Harmainen, H., Lehtola, J., and Hockerstedt, K. Toxic acute hepatitis and hepatic fibrosis after consumption of chaparral tablets. Scand.J Gastroenterol. 2004;39(11):1168-1171. PubMed
Leonforte, J. F. Contact dermatitis from Larrea (creosote bush). J Am Acad.Dermatol. 1986;14(2 Pt 1):202-207. PubMed
Alderman, S., Kailas, S., Goldfarb, S., Singaram, C., and Malone, D. G. Cholestatic hepatitis after ingestion of chaparral leaf: confirmation by endoscopic retrograde cholangiopancreatography and liver biopsy. J Clin.Gastroenterol. 1994;19(3):242-247.
Clark, F. Chaparral-induced toxic hepatitis: California and Texas, 1992. MMWR Morb Mortal Wkly Rep. 1992;41:812-814. DOI

Keep reading

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

Brand directory

Brands that make products with Chaparral

30 brands in our database make a supplement containing Chaparral.

5 Chinese Elements 10 products Barlow Herbal 13 products BioGenesis Nutraceuticals 87 products BN Baseline Nutritionals 28 products Cedar Bear 69 products Christopher's Original Formulas 140 products Doctor Morse's Healing Herbs 47 products Dr. Morse's Cellular Botanicals 79 products Dr. Schulze's 11 products Earth Friend Herb Co. 66 products Energetix 283 products Flower Essence Services 386 products GHC Global Healing Center 32 products Global Healing Center 98 products Herb Pharm 3,320 products Herbal Terra 3,138 products Herbally Grounded 81 products InfoWars Life 46 products Khroma Herbal Products 19 products LarreaRx 1 product Maine Coast Herbals 33 products New Body 1 product New Sun 518 products OL Olympian Labs Incorporated 144 products

Product directory

Supplement products with Chaparral

84 products in our database contain Chaparral. Open any to see its full ingredient list and every drug interaction we check.

Pharmacist Counseling Corner

Chaparral: Common Questions

Does Chaparral interact with prescription medications?

Yes. We list 372 medications with a known interaction with Chaparral. Use the checker above to see how Chaparral interacts with a specific drug.

How are Chaparral interactions rated?

Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.

Is it safe to take Chaparral with my medications?

It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.

Where does this Chaparral interaction information come from?

Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.

Is Chaparral safe to take?

No, it is not considered safe. Chaparral has been linked to serious liver and kidney damage, and the FDA has warned people not to use products containing it.

What is Chaparral used for?

It has traditionally been used for pain, inflammation, skin problems, and as a 'detox' or general tonic, but there is no reliable evidence that it works for any of these, and it carries real safety risks.

Can I take Chaparral while pregnant or breastfeeding?

No. There is no safety data and a known risk of toxicity, so Chaparral should be avoided during pregnancy and breastfeeding.

Can Chaparral cure cancer?

There is no good scientific evidence that Chaparral treats or cures cancer. Claims like this are not supported, and using Chaparral can be dangerous to your health.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Keep exploring

Products that contain Chaparral

A rotating sample of real supplements in our database that list Chaparral — open any to see its full ingredients and every drug interaction we check.

See all 84 products with Chaparral →

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