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Dietary supplement

Cat's Claw Extract Powder 500 mg Ingredients & Drug Interactions

by BulkSupplements.com

Powder Category: Botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Cat's Claw Extract Powder 500 mg is a dietary supplement by BulkSupplements.com 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 Cat's Claw Root Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Cat's Claw Extract Powder 500 mg by BulkSupplements.com

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

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: cat's claw root extract at 500 mg per dose. Cat's claw is a woody vine from the Amazon rainforest; its extract is concentrated from the root.

The only other ingredient listed is maltodextrin, an inactive filler used to standardize the powder.

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: Osteoarthritis, rheumatoid arthritis, and inflammation support.
  • We looked for evidence on: Osteoarthritis, Rheumatoid arthritis (RA), Inflammatory bowel disease (IBD), Joint inflammation, Immune support.
  • 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 effectiveness ratings we hold for cat's claw are insufficient—meaning the scientific evidence doesn't yet establish whether it works for any of the conditions it's marketed for. These include allergic rhinitis (hay fever), Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue syndrome.

That doesn't mean it's ineffective; it means we don't have strong clinical trial data to confirm it.

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. In one clinical trial of patients with advanced cancer, anemia occurred in about 12% of those taking it, and a small number experienced leukopenia (low white blood cells) and thrombocytopenia (low platelets).

Other trial participants reported headache, fatigue, insomnia, and neuropathy (nerve pain), though it's unclear whether these were due to cat's claw or the patients' underlying disease. Several case reports have linked cat's claw to kidney injury, including acute kidney failure and nephritis (kidney inflammation).

The safety data advises against use during pregnancy—cat's claw has a traditional history as an abortifacient, and there's no safety data in pregnancy. Avoid it while breastfeeding as well, since safety information is insufficient.

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 taking this product, check your medications against these drug types: blood pressure drugs and calcium channel blockers (risk of dangerously low blood pressure), CYP3A4-metabolized drugs like many statins and some cancer medications (levels may rise or fall), blood thinners and antiplatelet drugs (increased bleeding risk), immune-suppressing medications (cat's claw may work against them), and the COVID-19 antiviral nirmatrelvir/ritonavir. Use the tool on this page to verify your exact prescriptions.

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 extract is used for a range of conditions, but the evidence to support those uses isn't established in our data. More importantly, it interacts with several medication classes—blood pressure drugs, blood thinners, immune suppressants, and others—so you'll need to run it through our medication checker before starting.

Skip it if you're pregnant or breastfeeding, and talk to your pharmacist if you take any prescription drugs.

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 Apr 24, 2025.

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 Extract Powder 500 mg, straight from the product label.

Brand BulkSupplements.com
Barcode (UPC) X001Q8HJEB
Net contents 250 Gram(s); 8.8 Ounce(s)
Market status On market
Date entered into DSLD Apr 24, 2025
DSLD ID 330534
Product type Botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy 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 Extract Powder 500 mg by BulkSupplements.com, 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:
500 mg
Maximum serving Sizes:
500 mg
Servings per container
500
UPC/BARCODE
X001Q8HJEB
IngredientAmount% DV
Cat's Claw Root Extract500 mg--

Other ingredients: Maltodextrin

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

Cat Claw Extract Powder 500 mg per serving

Brand IP Statement(s)

BulkSupplements.com Clean & Pure Bulk Supplements

Formulation

Color may vary

Free of: Added sugar, soy, dairy, yeast, gluten, additives

FDA Disclaimer Statement

Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Always consult a physician before taking any dietary supplement.

Keep out of reach of children.

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 500mg (about 1/5 tsp) once or twice daily, or as directed by a physician.

Storage

Contents are sold by weight, not volume. Settling may occur. Store in a dry, cool place.

General Statements

Use an accurate milligram scale. New

See for yourself

Cat's Claw Extract Powder 500 mg by BulkSupplements.com label

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

What’s inside

The Ingredients in Cat's Claw Extract Powder 500 mg by BulkSupplements.com

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

Serving size500 mg Dosage formPowder Servings per container500 Amounts shown are per serving.

Cat's Claw Root Extract

Interacts with
962 drugs
500 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...

Cat's Claw Root Extract monograph & interactions

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

Interaction report

Cat's Claw Extract Powder 500 mg by BulkSupplements.com Drug Interactions

Want to check YOUR meds against Cat's Claw Extract Powder 500 mg?

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

Each ingredient & the kinds of drugs it affects

For each ingredient in Cat's Claw Extract Powder 500 mg 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.

Cat's Claw Root 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
The maker

Brand information

Manufacturer and brand details for Cat's Claw Extract Powder 500 mg, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Rd
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

Cat's Claw Extract Powder 500 mg by BulkSupplements.com: Common Questions

Does Cat's Claw Extract Powder 500 mg by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, Cat's Claw Extract Powder 500 mg 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 Extract Powder 500 mg 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 cat's claw if I'm pregnant or breastfeeding?
No. Cat's claw has a traditional history as an abortifacient and lacks safety data in pregnancy, so it's advised against. It's also not recommended while breastfeeding because there isn't enough safety information. Talk with your doctor if you're considering it while trying to conceive or nursing.
What side effects has cat's claw caused?
In clinical trials, anemia showed up in about 12% of people taking it, and a small number developed low white blood cells or low platelets. Some participants reported headache, fatigue, insomnia, and nerve pain. There are also case reports linking it to kidney injury, so if you have kidney disease or lupus, be especially cautious.
Does cat's claw actually work for the conditions it claims to help?
The evidence we hold is insufficient. For conditions like hay fever, Alzheimer's, asthma, osteoporosis, cancer, and chronic fatigue syndrome, we don't yet have strong clinical trial data showing cat's claw works. That doesn't mean it's useless—it means the science hasn't caught up yet.
How long can I safely take cat's claw?
It's generally well tolerated in the short term for healthy adults, but long-term safety hasn't been well studied. If you're thinking of taking it regularly for weeks or months, talk with your pharmacist about what we know and don't know.
Will cat's claw interfere with my COVID-19 antiviral medication?
Possibly. Cat's claw may speed up how your body breaks down nirmatrelvir (the active drug in Paxlovid), potentially making it less effective. If you're taking Paxlovid, check with your pharmacist or doctor before adding cat's claw.

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 Extract Powder 500 mg label
Go deeper

The Full Monographs Behind Cat's Claw Extract Powder 500 mg’s Ingredients

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

Sources

Sources & How We Checked

Cat's Claw Extract Powder 500 mg'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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