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Dietary supplement

Cat's Claw Ingredients & Drug Interactions

by Herbal Terra

Cat's Claw label
See full label image
Liquid Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Cat's Claw against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Cat's Claw is a dietary supplement by Herbal Terra with 1 active ingredient. Its ingredients are commonly taken for osteoarthritis and rheumatoid arthritis, inflammation, immune support.Based on those ingredients, 962 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Cat's Claw by Herbal Terra

Ask about any prescription or over-the-counter medication and we check it for interactions with Cat's Claw by Herbal Terra — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Cat's Claw by Herbal Terra

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 12, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract. The only other ingredient listed is menstruum, which is the liquid used to prepare the extract.

Cat's Claw has been used traditionally in herbal medicine, and its active compounds include alkaloids like rhynchophylline that appear to affect blood pressure, immune function, and how your body processes certain drugs.

Does it work?

Couldn't assess
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

This is a single-ingredient Cat's Claw product and its label doesn't state a use — see Cat's Claw's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence for Cat's Claw isn't established yet in the data we hold. The product is sometimes promoted for allergic rhinitis (hay fever), Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue syndrome, but we don't have reliable evidence to support any of these uses.

If you're considering it for a specific health concern, talk with your pharmacist or doctor about what the current science actually shows.

The evidence, ingredient by ingredient Cat's Claw

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Cat's Claw is generally well tolerated in the short term for healthy adults, but how safe it is over the long haul isn't well studied. You should avoid it during pregnancy — it has a history of traditional use as an abortifacient and we don't have safety data to say otherwise.

Skip it while breastfeeding too, since we don't know enough about whether it passes into breast milk or what it might do. In one clinical study, some patients developed low red blood cell counts (anemia), low white blood cell counts (leukopenia), and low platelet counts (thrombocytopenia) — though those patients had advanced cancer with no other treatment options, so it's hard to pin down what caused what.

Several case reports also link cat's claw to kidney injury, including acute kidney failure in one person with lupus and acute interstitial nephritis (kidney inflammation) in another. Headache, fatigue, insomnia, and nerve damage (neuropathy) were reported in a small number of study participants.

Side effects, ingredient by ingredient Cat's Claw

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Cat's Claw.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs.
  • For scale: 963 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take Herbal Terra's Cat's Claw, double-check with your pharmacist if you're on blood thinners (anticoagulants or antiplatelets like warfarin or aspirin), blood pressure medications (antihypertensives or calcium channel blockers), drugs that your liver breaks down via CYP3A4 (a huge category including many statins and some cancer drugs), immune-suppressing medications, or nirmatrelvir/ritonavir (Paxlovid). All of these carry Moderate-severity interaction risks.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Cat's Claw may be worth considering if you're interested in herbal immune support, but it's not for everyone. If you take blood thinners, blood pressure drugs, or any CYP3A4-metabolized medication, you need to check with your pharmacist first — the interaction risks are real.

Steer clear if you're pregnant or breastfeeding, and keep an eye out for any signs of bleeding, dizziness, or kidney problems.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Nov 21, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Cat's Claw, straight from the product label.

Brand Herbal Terra
Barcode (UPC) 7429523278278
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Nov 21, 2020
DSLD ID 233946
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Cat's Claw by Herbal Terra, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 mL
Maximum serving Sizes:
1 mL
Servings per container
120
UPC/BARCODE
7429523278278
IngredientAmount% DV
wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract970 mg--

Other ingredients: Menstruum

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Formulation

Origin of plant material: Peru.

Manufactured in the USA in an FDA registered facility

Sugar free

Dried herb/menstruum ratio: 1:3 Expertly extracted Laboratory tested 330 mg/1 mL Premium product Super concentrated liquid herbal extract

Non GMO

No artificial ingredients, GMO, gluten, color additives, fillers, preservatives or binders. Natural Gluten Free

Suggested/Recommended/Usage/Directions

Direction Shake well before use. Adults take up to 30 drops (1 mL, one full squeeze of the dropper bulb) in 3-4 fl. oz of juice or water up to 4 times a day. We recommend to seek expert medical advice before taking this or any other herbal supplements.

FDA Disclaimer Statement

Notice This product has not been evaluated by the FDA and is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Caution May have contraindications.

Do not use if you are allergic to any ingredients.

Consult a physician before using during pregnancy, if nursing, or if you are on any medications.

Keep out of the reach of children.

Storage

Store in a cool, dry, dark place.

Formula

Uncaria tomentosa

FDA Statement of Identity

Herbal Supplement

Seals/Symbols

Made in USA Made in an FDA registered facility Natural Gluten Free

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Cat's Claw by Herbal Terra label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Cat's Claw label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Cat's Claw by Herbal Terra

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container120 Amounts shown are per serving.

Wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract

Interacts with
962 drugs
970 mg per serving

Cat's claw is a South American vine traditionally used for inflammation, joint pain, and immune support. Some small studies hint it may help with arth...

Wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract monograph & interactions

Other (inactive) ingredients: Menstruum. These complete the product’s ingredient list but are not active constituents.

Interaction report

Cat's Claw by Herbal Terra Drug Interactions

Want to check YOUR meds against Cat's Claw?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
962Drugs
962 Moderate

Ingredients driving the most interactions

wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract 962

Individual Drug Interactions

The ingredients in Cat's Claw interact with 962 drugs. Click any drug to see the details.

1 of the 1 ingredient in Cat's Claw interact with drugs. Each result below shows which ingredient is responsible. wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Cat's Claw with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract6 drug types · 962 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, cat's claw may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Cat's claw contains rhynchophylline and isorhynchophylline. Animal research suggests that these alkaloids can inhibit platelet aggregation. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking cat's claw with antihypertensive drugs might increase the risk of hypotension.
Cat's claw contains rhynchophylline. In vitro and animal research suggests that rhynchophylline can lower blood pressure. This interaction has not been reported in humans.

Likelihood Probable Evidence D
Calcium Channel Blockers

Theoretically, taking cat's claw with calcium channel blockers might increase the risk of hypotension.
Cat's claw contains various alkaloids, including rhynchophylline, isorhynchophylline, corynoxeine, and isocorynoxiene. Animal research suggests that these alkaloids can lower blood pressure by acting as calcium channel blockers. This interaction has not been reported in humans.

Likelihood Probable Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, cat's claw might increase or decrease the levels and effects of drugs metabolized by CYP3A4.
Cat's claw may affect the clearance of drugs metabolized by CYP3A4. In vitro research shows that cat's claw can inhibit CYP3A4 enzymes. In one case report, a patient taking cat's claw (at an unspecified dose) experienced increased serum levels of atazanavir, ritonavir, and saquinavir, all of which are CYP3A4 substrates. Levels returned to normal 15 days after discontinuation of the cat's claw supplement, suggesting inhibition of CYP3A4 by cat's claw. In contrast, animal research suggests that rhynchophylline, an alkaloid contained in cat's claw, induces CYP3A expression and accelerates the metabolism of nirmatrelvir, the active component in the nirmatrelvir/ritonavir combination product.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, cat's claw might interfere with immunosuppressive therapy.
In human and laboratory research, cat's claw has been shown to have immunostimulating activity. It stimulates phagocytosis and increases respiratory cellular activity and the mobility of leukocytes. Theoretically, this could interfere with the activity of immunosuppressant medications.

Likelihood Possible Evidence D
Nirmatrelvir/Ritonavir (Paxlovid)

Theoretically, cat's claw may decrease the levels of nirmatrelvir.
Cat's claw contains rhynchophylline. Animal research suggests that this alkaloid induces CYP3A expression, thereby accelerating the metabolism of nirmatrelvir, the active component in the nirmatrelvir/ritonavir combination product. This interaction has not been reported in humans.

Likelihood Possible Evidence D
wildcrafted Cat's Claw (Uncaria tomentosa) dried inner bark liquid extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Cat's Claw, from the product label.

Herbal Terra

See all Herbal Terra products
Name
Herbal Terra
Pharmacist Counseling Corner

Cat's Claw by Herbal Terra: Common Questions

Does Cat's Claw by Herbal Terra interact with any medications?
Yes. Based on its ingredients, Cat's Claw has a known interaction with 962 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Cat's Claw contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is Cat's Claw safe to take if I'm pregnant?
No — the safety data advises against it. Cat's Claw has a traditional history of use as an abortifacient, and we don't have reliable safety information for pregnancy. Talk with your doctor or pharmacist before considering it.
Can I take this while breastfeeding?
We advise against it due to insufficient safety information. We don't know enough about whether cat's claw passes into breast milk or what effects it might have on a nursing infant. Ask your pharmacist or doctor before starting.
What side effects have been reported with Cat's Claw?
In a clinical study, some patients reported headache, fatigue, insomnia, and nerve pain. More concerning, a small number developed low blood cell counts, and several case reports link cat's claw to kidney injury. Since long-term safety isn't well studied, keep watch for unusual bleeding, dizziness, or changes in how you feel.
Does Cat's Claw actually work for any health condition?
The evidence isn't established in our data. It's sometimes promoted for hay fever, Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue, but we don't have reliable evidence to back those claims. Ask your pharmacist what the research currently shows.
Why does Cat's Claw interact with so many medications?
The main reason is that cat's claw can affect how your liver breaks down drugs, particularly through an enzyme system called CYP3A4. It also contains compounds that lower blood pressure and slow clotting — both of which can amplify the effects of medications that do similar things. That's why 963 individual medications are potentially affected.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Cat's Claw label
Go deeper

The Full Monographs Behind Cat's Claw’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Cat's Claw

Interacts with 962 drugs

Cat's claw is a South American vine traditionally used for inflammation, joint pain, and immune support. Some small studies hint it may help with arthritis symptoms, but the overall evidence...

Read the full Cat's Claw monograph →
Sources

Sources & How We Checked

Cat's Claw's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 16 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Cat's Claw 16 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  3. Sandoval M, Charbonnet RM, Okuhama NN, et al. Cat's claw inhibits TNFalpha production and scavenges free radicals: role in cytoprotection. Free Radic Biol Med 2000;29:71-78.
  4. Müller AC, Kanfer I. Potential pharmacokinetic interactions between antiretrovirals and medicinal plants used as complementary and African traditional medicines. Biopharm Drug Dispos. 2011;32(8):458-70. PubMed
  5. Sheng, Y., Bryngelsson, C., and Pero, R. W. Enhanced DNA repair, immune function and reduced toxicity of C-MED-100, a novel aqueous extract from Uncaria tomentosa. J Ethnopharmacol. 2000;69(2):115-126. PubMed
  6. Lamm, S., Sheng, Y., and Pero, R. W. Persistent response to pneumococcal vaccine in individuals supplemented with a novel water soluble extract of Uncaria tomentosa, C-Med-100. Phytomedicine 2001;8(4):267-274.
  7. Sheng, Y., Li, L., Holmgren, K., and Pero, R. W. DNA repair enhancement of aqueous extracts of Uncaria tomentosa in a human volunteer study. Phytomedicine 2001;8(4):275-282.
  8. Chen, C. X., Jin, R. M., Li, Y. K., Zhong, J., Yue, L., Chen, S. C., and Zhou, J. Y. Inhibitory effect of rhynchophylline on platelet aggregation and thrombosis. Zhongguo Yao Li Xue.Bao. 1992;13(2):126-130.
  9. Flythe, J. E., Rueda, J. F., Riscoe, M. K., and Watnick, S. Silicate nephrolithiasis after ingestion of supplements containing silica dioxide. Am.J.Kidney Dis. 2009;54(1):127-130. PubMed
  10. Zhou, J. and Zhou, S. Antihypertensive and neuroprotective activities of rhynchophylline: the role of rhynchophylline in neurotransmission and ion channel activity. J.Ethnopharmacol. 10-28-2010;132(1):15-27. PubMed
  11. Zhou, J. Y. and Zhou, S. W. Isorhynchophylline: A plant alkaloid with therapeutic potential for cardiovascular and central nervous system diseases. Fitoterapia 2012;83(4):617-626. PubMed
  12. Hemingway, S. R. and Phillipson, J. D. Proceedings: Alkaloids from S. American species of Uncaria (Rubiaceae). J.Pharm.Pharmacol. 1974;26 Suppl:113P.
  13. Hilepo, J. N., Bellucci, A. G., and Mossey, R. T. Acute renal failure caused by 'cat's claw' herbal remedy in a patient with systemic lupus erythematosus. Nephron 1997;77(3):361. PubMed
  14. De Paula LCL, Fonseca F, Perazzo F, et al. Uncaria tomentosa (cat's claw) improves quality of life in patients with advanced solid tumors. J Altern Complement Med. 2015;21(1):22-30.
  15. Portalatin G, Shettigar S, Carrion-Rodriguez A, et al. Ketogenic-Diet Shake Containing Uncaria tomentosa-Associated Acute Interstitial Nephritis. Case Rep Nephrol Dial 2022;12(3):219-225.
  16. Lei S, Guo A, Lu J, et al. Activation of PXR causes drug interactions with Paxlovid in transgenic mice. Acta Pharm Sin B 2023;13(11):4502-4510. PubMed

See these in context on the Cat's Claw monograph →

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.

© 2021 Therapeutic Research Center, LLC

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