Cat's Claw
Cat's Claw (Uncaria tomentosa)
Amazon rainforest vine with immune-modulating and anti-inflammatory properties, traditionally used for arthritis and infections.
Cat's Claw is a woody vine from the Amazon rainforest named for its hook-like thorns. Used by indigenous peoples for millennia, it contains oxindole alkaloids and other compounds with immune-modulating, anti-inflammatory, and antioxidant effects. Research supports benefits for osteoarthritis, rheumatoid arthritis, and immune function.
Mechanisms of Action
Immune Modulation
Enhances and regulates immune function
Anti-Inflammatory
Reduces inflammatory mediators
Antioxidant
Protects against oxidative damage
Recommended Dose
250-350mg standardized extract or 1-3g dried bark, 2-3x daily
Optimal Timing
- With meals
Take with food
Best Form
Standardized extract (3% oxindole alkaloids)
Alternatives: Dried bark capsules, Tea, Tincture
Two species exist — Uncaria tomentosa is most researched. Some products use U. guianensis.
Duration
Minimum: 4 weeks
Optimal: 12 weeks
Cycling: 8-12 weeks on, 2-4 weeks off recommended for long-term use.
Note: Taking with food reduces potential GI upset. Split into 2-3 doses for best results.
Personalized Dosage Calculator
Get a dosage recommendation tailored to your body weight, age, goals, and health profile.
Set up your health profile for personalized recommendations
Joint Support
Reduced arthritis symptoms
Immune Enhancement
Improved immune function
Inflammation Reduction
Lower inflammatory markers
Avoid — traditionally contraindicated
Avoid or use under medical supervision
Who Should NOT Take This
- Autoimmune diseases (may stimulate immune system)
- Before surgery (stop 2 weeks prior)
- Organ transplant recipients
Drug Interactions
May increase bleeding risk
May counteract immunosuppression
May have additive blood pressure lowering effects
May affect drug metabolism
Possible Side Effects
Tip: Take with food
Tip: Reduce dose
Tip: Usually resolves
Warnings
- Avoid in autoimmune diseases (may stimulate immune system)
- Stop 2 weeks before surgery
- Not for transplant recipients on immunosuppressants
Top studies from 40+ peer-reviewed papers
Marques O et al. • International journal of molecular sciences (2025)
“The present work emphasizes the current pharmacological properties of Uncaria tomentosa, evidencing its therapeutic benefits and encouraging further research on this medicinal plant.”
Key Findings:
- The present paper reviews research progress relating to the ethnobotany, phytochemistry and pharmacology of Ut, and some promising research routes are also discussed.
- We highlight the centrality of its different biological activities, such as antioxidant, anti-inflammatory, antiproliferative, antiviral, and antinociceptive, among others.
- The present work emphasizes the current pharmacological properties of Uncaria tomentosa, evidencing its therapeutic benefits and encouraging further research on this medicinal plant.
Roberts KE et al. • The Cochrane database of systematic reviews (2022)
“AIMSS are chronic and complex symptoms with a significant impact on women with early breast cancer taking AI.”
Key Findings:
- The two studies, investigating vitamin D and omega-3 fatty acids, showed a treatment effect with 95% CIs that did not include an MCID for pain.
- Systemic therapies may have little to no effect on grip strength (RR 1.08, 95% CI 0.37 to 3.17; 1 study, 137 women) or on women continuing to take their AI (RR 0.16, 95% 0.01 to 2.99; 1 study, 147 women).
- The evidence suggests little to no effect on HRQoL and BCS-QoL from baseline to the end of intervention (the same single study; 44 women, both quality of life outcomes showed a treatment effect with 95% CIs that did include an MCID).
- The evidence is very uncertain for outcomes assessing incidence of AIMSS (RR 0.82, 95% CI 0.63 to 1.06; 2 studies, 240 women) and the safety of systemic therapies (4 studies, 344 women; very low-certainty evidence).
Carvalho-Silva JM et al. • The Journal of prosthetic dentistry (2025)
“Gels formulated with natural antimicrobials such as Z. multiflora, U. tomentosa, P. granatum, propolis, and clove and cinnamon showed higher or similar antimicrobial efficacy to conventional antifungals in the treatment of DS.”
Key Findings:
- Gels formulated with natural antimicrobials such as Z. multiflora, U. tomentosa, P. granatum, propolis, and clove and cinnamon showed higher or similar antimicrobial efficacy to conventional antifungals in the treatment of DS.
- The biocompatibility of experimental gels based on natural agents should be evaluated.
- Further research warranted to confirm findings
Plazas E et al. • Molecules (Basel, Switzerland) (2025)
“These findings highlight the immense potential of bioactive compounds from tropical American plants as modulators of immune-inflammatory pathways, providing a foundation for developing effective therapeutic agents to counteract the severe effects of cytokine storms.”
Key Findings:
- Key polyphenols, like quercetin and luteolin, found in plants such as Achyrocline satureioides and Mangifera indica demonstrate the downregulation of NF-κB and inhibition of pro-inflammatory cytokines.
- Alkaloids, such as berberine and mitraphylline, isolated from Berberis species and Uncaria tomentosa, respectively, have shown potent effects in suppressing nitric oxide production and regulating inflammasomes.
- Terpenoids, including parthenolide from Tanacetum parthenium and curcumol from Curcuma longa, exhibit multitarget activity, reducing cytokine levels and inhibiting key inflammatory enzymes like COX-2 and iNOS.
- These findings highlight the immense potential of bioactive compounds from tropical American plants as modulators of immune-inflammatory pathways, providing a foundation for developing effective therapeutic agents to counteract the severe effects of cytokine storms.
Inácio Silveira DQ et al. • The Journal of prosthetic dentistry (2023)
“Certainty in the body of evidence that natural products might be appropriately used in the treatment of denture stomatitis is low.”
Key Findings:
- Certainty in the body of evidence that natural products might be appropriately used in the treatment of denture stomatitis is low.
- Well-designed randomized controlled trials are still needed to evaluate the topic better because there is high heterogeneity among the studies.
- Further research warranted to confirm findings
Study Type Distribution
Goals This Supplement Supports
This information is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare provider before starting any supplement.