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Dietary supplement

Royal Cat's Claw Ingredients & Drug Interactions

by Whole World Botanicals

Royal Cat's Claw label
See full label image
Other (e.g. Tea Bag) 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 Royal 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

Royal Cat's Claw is a dietary supplement by Whole World Botanicals 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 Uncaria tomentosa. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Royal Cat's Claw by Whole World Botanicals

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

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HelloPharmacist Scorecard of Royal Cat's Claw by Whole World Botanicals

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 11, 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.

Royal Cat's Claw is a single-ingredient product: cat's claw (Uncaria tomentosa), a woody vine from the Amazon traditionally used in herbal medicine. It contains alkaloids like rhynchophylline and isorhynchophylline, which are responsible for most of its known effects on blood pressure, clotting, and immune function.

There are no inactive ingredients listed for this product.

Does it work?

Insufficient evidence
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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: supports body's natural defenses against disease.
  • We looked for evidence on: Rheumatoid arthritis (RA), Osteoarthritis, Inflammatory bowel disease (IBD), immune function, inflammation, general wellness.
  • The closest evidence on file: Cat's Claw is rated "Insufficient Reliable Evidence To Rate" for Inflammatory bowel disease (IBD) (Natural Medicines).
  • Also on file: Cat's Claw is rated "Insufficient Reliable Evidence To Rate" for Osteoarthritis, Rheumatoid arthritis (RA).

The evidence for cat's claw is not established in our data. We hold ratings for allergic rhinitis (hay fever), Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue syndrome — and for all of these, the evidence is listed as insufficient to rate.

If you're considering cat's claw for a specific condition, talk with your pharmacist or doctor about what the current research actually supports.

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 long-term safety hasn't been well studied. Avoid it during pregnancy — traditional use as an abortifacient and lack of safety data make it unsafe.

Don't use it while breastfeeding either due to insufficient safety information. Case reports link cat's claw to kidney injury, including acute kidney failure and kidney inflammation in people with certain conditions.

One clinical trial in patients with advanced cancer reported anemia in 12%, and leukopenia (low white blood cells) and thrombocytopenia (low platelets) each in 2%; however, because there was no control group, it's unclear whether cat's claw or the underlying cancer caused these. Headache, fatigue, insomnia, and nerve damage also appeared in that same trial population, with the same caveat.

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.

Check with us before taking this if you're on blood thinners or antiplatelet drugs (warfarin, aspirin, clopidogrel), blood pressure or heart medications (especially calcium channel blockers), immunosuppressants, CYP3A4-metabolized drugs, or Paxlovid. All are Moderate-severity concerns with cat's claw.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with insufficient evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Cat's claw is a single-ingredient supplement with potential interactions affecting nearly 1,000 medications — mainly blood thinners, blood pressure drugs, and immune suppressants. If you take any regular medication, especially heart or blood-clotting drugs, check with us before you start.

Pregnant or breastfeeding? This one isn't for you.

A pharmacist can help you sort out whether it's right for your specific situation.

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 Sep 22, 2022.

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 Royal Cat's Claw, straight from the product label.

Brand Whole World Botanicals
Barcode (UPC) 691195005903
Net contents 140 Gram(s); 4.9 Ounce(s)
Market status On market
Date entered into DSLD Sep 22, 2022
DSLD ID 276149
Product type Botanical
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Royal Cat's Claw by Whole World Botanicals, 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:
0.5 Cup(s)
Maximum serving Sizes:
0.5 Cup(s)
Servings per container
93
UPC/BARCODE
691195005903
IngredientAmount% DV
Uncaria tomentosa1.5 Gram(s)--

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.
Formula

Scientific evidence: Numerous published studies suggest that Uncaria tomentosa promotes killer T-cell production, supports repair of DNA in cells & inhibits C-reactive protein. These impressive research results were obtained from Cat's Claw as it comes from nature, containing all of its alkaloids, both POA & TOA. Uncaria tomentosa Traditional adaptogenic herb from the Amazon

Formulation

Supports your body's natural defenses against disease

This product is wildcrafted & sustainably harvested.

No pesticides have been used or irradiation applied in importation.

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions for use: Drink one-half cup of tea at least 15 minutes before eating or two hours after eating 2-4 times daily or as directed by your health care practitioner. Do not take at bed time if it interferes with your sleep. As with most herbs, it is advised to cycle on and off rather than to take it continuously. For example: 3 months on and one month off or 4 days on and 3 days off (weekly).

To prepare: Put 8 tsps. of tea into 5 cups of boiling water. Reduce heat and simmer (barely boil) the tea in a pot without a lid for 30 minutes. Strain. Makes 4 cups of tea. It tastes best if taken hot or very cold. Ice cubes and stevia may be added.

For those with sensitive stomachs: add 1/2 tsp. of lemon juice to each cup of water used in preparing tea. This will ind up most tannic acid and make tea less astringent.

Precautions

Do not take at bed time if it interferes with your sleep.

Warning: Keep out of the reach of children.

Not for use by women who are pregnant or nursing.

Storage

Tea may be stored in refrigerator in glass (or plastic) jar with a lid for up to one week.

General Statements

Part of the profits of WWB are used to reclaim rainforest land and to assist native people in growing medicinal plants as a source of livelihood.

FDA Disclaimer Statement

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

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

See for yourself

Royal Cat's Claw by Whole World Botanicals label

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

Royal 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 Royal Cat's Claw by Whole World Botanicals

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

Serving size0.5 Cup(s) Dosage formOther (e.g. Tea Bag) Servings per container93 Amounts shown are per serving.

Uncaria tomentosa

Interacts with
962 drugs
1.5 Gram(s) 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...

Uncaria tomentosa monograph & interactions
Interaction report

Royal Cat's Claw by Whole World Botanicals Drug Interactions

Want to check YOUR meds against Royal 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

Uncaria tomentosa 962

Individual Drug Interactions

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

1 of the 1 ingredient in Royal Cat's Claw interact with drugs. Each result below shows which ingredient is responsible. Uncaria tomentosa

Each ingredient & the kinds of drugs it affects

For each ingredient in Royal 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.

Uncaria tomentosa6 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
Uncaria tomentosa full monograph & interactions
The maker

Brand information

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

Whole World Botanicals

See all Whole World Botanicals products
Name
Whole World Botanicals, Inc.
City
NY
State
NY
ZipCode
10032
Phone Number
(646) 290-8651
Web Address
www.wholeworldbotanicals.com
Pharmacist Counseling Corner

Royal Cat's Claw by Whole World Botanicals: Common Questions

Does Royal Cat's Claw by Whole World Botanicals interact with any medications?
Yes. Based on its ingredients, Royal 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?
Royal 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.
Can I take Royal Cat's Claw while I'm pregnant or nursing?
No. Cat's claw is unsafe during pregnancy because of its traditional use as an abortifacient and lack of safety data. Avoid it while breastfeeding too — there isn't enough safety information. Talk with your doctor if you're pregnant, planning to become pregnant, or nursing.
What side effects should I watch for?
Case reports have linked cat's claw to kidney injury. Clinical trial data from cancer patients (the only controlled data we have) reported anemia, low white blood cell counts, low platelets, headache, fatigue, insomnia, and nerve damage — though because of the trial's design and patient population, it's unclear what was due to cat's claw itself. If you develop unusual bruising, bleeding, or changes in urine or kidney function, contact your doctor.
How long is it safe to take cat's claw?
Short-term use in healthy adults is generally well tolerated. Long-term safety hasn't been well studied, so we don't have good data on ongoing use. Ask your pharmacist or doctor about how long you should take it.
Does cat's claw actually work for anything?
The evidence isn't established in our data. We have insufficient evidence to rate it for hay fever, Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue syndrome. If you're considering it for a particular condition, talk with your doctor or pharmacist about what research actually supports its use.

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.

Royal Cat's Claw label
Go deeper

The Full Monographs Behind Royal 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

Royal 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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