Interactions on record — worth a quick check against your medications. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Cat's Claw Ingredients & Drug Interactions

by Herb Xtra

Cat's Claw label
See full label image
Capsule Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 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 Herb Xtra with 3 active ingredients. Its ingredients are commonly taken for joint and bone health, skin, hair, and nail support, source of dietary protein.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. 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 Herb Xtra

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

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HelloPharmacist Scorecard of Cat's Claw by Herb Xtra

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

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 3 active ingredients.

Herb Xtra's Cat's Claw comes in a 3-ingredient formula. The active ingredient is cat's claw (Uncaria tomentosa), a vine from the Amazon that's used in traditional medicine.

The capsule is made from gelatin, and the formula contains water as well. There are no other inactive ingredients listed.

Does it work?

Not established
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 established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: herbal supplement for general wellness.
  • We looked for evidence on: Osteoarthritis, Rheumatoid arthritis (RA), Inflammatory bowel disease (IBD), Joint pain, inflammation, immune function — and 1 related terms.
  • 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).
  • Also on file: Gelatin is rated "Insufficient Reliable Evidence To Rate" for Osteoarthritis, Joint pain, Rheumatoid arthritis (RA).

The effectiveness data we hold for cat's claw doesn't establish that it works for the conditions listed — allergic rhinitis, Alzheimer disease, asthma, osteoporosis, cancer, and chronic fatigue syndrome all show insufficient reliable evidence to rate. That means the science isn't settled yet on whether it helps with these.

Gelatin's effectiveness is also not established in our data for the conditions listed. If you're considering this product for a specific health goal, talk with your pharmacist about what the current research actually shows.

The evidence, ingredient by ingredient Gelatin 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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Cat's claw is generally well tolerated over the short term in healthy adults, but long-term safety isn't well studied. Case reports link it to kidney injury in a small number of people, including one with lupus and another consuming it in keto shakes.

A clinical trial in patients with advanced cancer found that 12% developed anemia, and smaller numbers developed low white or platelet counts — though the study was uncontrolled and those patients had serious illness, so it's unclear what was due to cat's claw itself. Headache, fatigue, insomnia, and nerve pain were also reported in small numbers in that same trial.

Gelatin is generally well tolerated when taken by mouth; belching, bloating, and indigestion can occur. Rare allergic reactions to gelatin are possible, including hives, swelling, wheezing, and in severe cases anaphylaxis — gelatin is used as a stabilizer in some vaccines like MMR and DPT.

Side effects, ingredient by ingredient Gelatin 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 2 matched ingredients 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 before taking if you're on blood thinners or antiplatelet drugs (like warfarin or clopidogrel) — cat's claw may increase bleeding risk. Blood pressure medications, including calcium channel blockers, could drop your pressure further.

If you take drugs broken down by CYP3A4 — a huge group including many statins and immunosuppressants — cat's claw may raise or lower their levels. Paxlovid (nirmatrelvir/ritonavir) may become less effective.

Use the medication checker below for your full list.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Cat's Claw by Herb Xtra may be worth considering if you're interested in traditional botanical support, but it interacts with a significant number of medications — especially blood thinners, blood pressure drugs, and certain antivirals. Long-term safety data is limited.

Before you take it, check your exact medications with the tool on this page, and talk with your pharmacist if you're on any prescription drugs or have kidney concerns.

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

Assessment coverage: 2 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 25, 2013.

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 Herb Xtra
Barcode (UPC) 777949998537
Net contents 100 Capsule(s); 450 mg
Market status On market
Date entered into DSLD Jan 25, 2013
DSLD ID 17610
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years)
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 Herb Xtra, 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 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
777949998537
IngredientAmount% DV
Gelatin0 NP--
Water0 NP--
Cat's Claw0 NP--

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.
Suggested/Recommended/Usage/Directions

Use: As a Herbal Supplement: 1 capsule 3 times daily with a glass of water.

General

H327600

Precautions

Caution: Not recommended (Cat's Claw - Uncaria tomentosa) for children, nursing or pregnant women.

Formula

Uncaria tomentosa

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

See for yourself

Cat's Claw by Herb Xtra 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 Herb Xtra

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Gelatin

No known
interactions
0 NP per serving

Gelatin is a protein made from animal collagen, used as a food, a capsule ingredient, and a supplement for joint, skin, and bone health. For most heal...

Gelatin monograph & interactions

Water

0 NP per serving

Cat's Claw

Interacts with
962 drugs
0 NP 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 monograph & interactions
Interaction report

Cat's Claw by Herb Xtra 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

Cat's Claw 962

Individual Drug Interactions

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

1 of the 3 ingredients in Cat's Claw interact with drugs. Each result below shows which ingredient is responsible. Cat's Claw

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.

Cat's Claw6 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
Cat's Claw full monograph & interactions
The maker

Brand information

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

Herb Xtra

See all Herb Xtra products
Name
GOURMET NUTRITION F.B. INC.
City
STE-JULIE
State
QUEBEC
ZipCode
J3E 1Z2
Pharmacist Counseling Corner

Cat's Claw by Herb Xtra: Common Questions

Does Cat's Claw by Herb Xtra 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 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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 it safe to take Cat's Claw during pregnancy?
No. The safety data advises against cat's claw in pregnancy because of its traditional use as an abortifacient and lack of safety studies. Talk with your doctor or pharmacist for personalized advice.
Is it safe while breastfeeding?
No. There isn't enough safety information, so it's best to avoid cat's claw while breastfeeding. Your pharmacist or doctor can help you weigh your options.
What are the most common side effects?
With gelatin (the capsule), belching, bloating, and indigestion can happen. Cat's claw itself is generally well tolerated short-term, though case reports have linked it to kidney injury in some people, and a trial found anemia and nerve issues in a small number of cancer patients.
How long can I safely take this?
Cat's claw is generally well tolerated over the short term in healthy adults, but we don't have good long-term safety data, so talk with your pharmacist about how long you're planning to use it.
Does cat's claw actually work for what it claims?
The evidence we hold shows insufficient reliable data to say whether cat's claw works for the conditions listed — allergies, Alzheimer disease, asthma, osteoporosis, cancer, or chronic fatigue. The science isn't settled yet.

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

Not sure if Cat's Claw is safe with your meds?

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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

Gelatin

Gelatin is a protein made from animal collagen, used as a food, a capsule ingredient, and a supplement for joint, skin, and bone health. For most health uses, the evidence is limited or mixe...

Read the full Gelatin monograph → 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 27 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.

Gelatin 11 references
  1. Lewis CJ. Letter to reiterate certain public health and safety concerns to firms manufacturing or importing dietary supplements that contain specific bovine tissues. FDA. Available at: www.cfsan.fda.gov/~dms/dspltr05.html.
  2. Schwick HG, Heide K. Immunochemistry and immunology of collagen and gelatin. Bibl Haematol 1969;33:111-25. PubMed
  3. Moskowitz RW. Role of collagen hydrolysate in bone and joint disease.Semin Arthritis Rheum 2000;30:87-99. PubMed
  4. Kelso JM. The gelatin story. J Allergy Clin Immunol 1999;103:200-2.
  5. Nakayama T, Aizawa C, Kuno-Sakai H. A clinical analysis of gelatin allergy and determination of its causal relationship to the previous administration of gelatin-containing acellular pertussis vaccine combined with diphtheria and tetanus toxoids. J Allerg PubMed
  6. Sakaguchi M, Inouye S. Anaphylaxis to gelatin-containing rectal suppositories. J Allergy Clin Immunol 2001;108:1033-4. PubMed
  7. PDR Electronic Library. Montvale, NJ: Medical Economics Company, Inc., 2001.
  8. de la Fuente Tornero E, Vega Castro A, de Sierra Hernández PÁ, et al. Kounis syndrome during anesthesia: Presentation of indolent systemic mastocytosis: A case report. A Case Rep. 2017;8(9):226-228. PubMed
  9. Ventura Spagnolo E, Calapai G, Minciullo PL, Mannucci C, Asmundo A, Gangemi S. Lethal anaphylactic reaction to intravenous gelatin in the course of surgery. Am J Ther. 2016;23(6):e1344-e1346. PubMed
  10. Li Y, He H, Yang L, Li X, Li D, Luo S. Therapeutic effect of Colla corii asini on improving anemia and hemoglobin compositions in pregnant women with thalassemia. Int J Hematol. 2016;104(5):559-565. PubMed
  11. Coury JR, Skaggs KF, Marciano GF, et al. Intraoperative Anaphylaxis to the Bovine Flowable Gelatin Matrix: A Report of 2 Cases. JBJS Case Connect 2022;12(1). PubMed

See these in context on the Gelatin monograph →

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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