Cats Claw
Uncaria tomentosa
TL;DR
Cat's claw has small but genuine randomised evidence for osteoarthritis pain and some rheumatoid arthritis data as an add-on. Chemotype matters: pentacyclic alkaloid extracts are the studied ones, and it interacts with several drug classes.
Ideal For
- Adults with knee osteoarthritis wanting a plant adjunct to standard care
- People with inflammatory joint pain not on immunosuppressive therapy
Avoid If
- You have had an organ transplant
- You take immunosuppressants for an autoimmune condition
- You are pregnant or breastfeeding
- You take a narrow-therapeutic-index CYP3A4 drug
Frequently Asked Questions
Overview
Cat's claw (Uncaria tomentosa) is a woody Amazonian vine whose inner bark contains oxindole alkaloids, quinovic acid glycosides and proanthocyanidins. Two chemotypes exist: pentacyclic oxindole alkaloids (POA), which are immunomodulatory, and tetracyclic alkaloids (TOA), which appear to antagonise POA activity - so standardisation matters more here than for most herbs. The clearest human evidence is a placebo-controlled trial in knee osteoarthritis where a freeze-dried water extract reduced pain with activity within one week without affecting resting pain or markers of safety. A 52-week trial in rheumatoid arthritis using a POA-standardised extract alongside sulfasalazine or hydroxychloroquine showed a modest reduction in the number of painful joints versus placebo. Mechanistically it inhibits TNF-alpha production and NF-kB activation at concentrations achievable in vitro, and some evidence supports DNA repair enhancement. Antiviral and cancer claims are preclinical only. The immunomodulatory activity that makes it interesting is also why transplant recipients and people on immunosuppressants should not take it.
How It Works
- Inhibits TNF-alpha production and NF-kB activation in immune cells
- Quinovic acid glycosides contribute anti-inflammatory activity independent of alkaloids
- Pentacyclic oxindole alkaloids modulate lymphocyte proliferation
- Antioxidant activity supports DNA repair in cultured cells
Supporting Research9 studies
Efficacy and safety of freeze-dried cats claw in osteoarthritis of the knee: mechanisms of action of the species Uncaria guianensis
Piscoya J, Rodriguez Z, Bustamante SA +3 more
Cats claw extract reduced knee pain associated with activity within one week compared with placebo, without significant changes in knee circumference or resting pain.
Early relief of osteoarthritis symptoms with a natural mineral supplement and a herbomineral combination: a randomized controlled trial
Miller MJ, Mehta K, Kunte S +2 more
All four groups showed improvement in WOMAC and VAS scores after 8 weeks (p < 0.001), in all 3 groups receiving sierrasil the magnitude of benefits were greater vs. placebo (WOMAC Total 38-43% vs. 27%) but this was not statistically significant.
Randomized double blind trial of an extract from the pentacyclic alkaloid-chemotype of Uncaria tomentosa for the treatment of rheumatoid arthritis
Mur E, Hartig F, Eibl G +1 more
Uncaria tomentosa extract added to standard therapy modestly reduced the number of painful joints compared with placebo, with no significant change in swollen joints or other measures.
Evaluation of different treatment methods against denture stomatitis: a randomized clinical study
Tay LY, Jorge JH, Herrera DR +2 more
U tomentosa gel had the same effect as 2% miconazole gel. U tomentosa gel is an effective topical adjuvant treatment for denture stomatitis.
Natural products for the treatment of denture stomatitis: A systematic review
Inácio Silveira DQ, Lia EN, Massignan C +1 more
Propolis, green tea, ginger, Zataria multiflora, chitosan, garlic, Artemisia, Schinus terebinthifolius Raddi, Uncaria tomentosa, Punica granatum, and Ricinus communis appeared to have similar efficacy and safety when compared with nystatin or miconazole.
Dietary supplement interactions with antiretrovirals: a systematic review
Jalloh MA, Gregory PJ, Hein D +2 more
Cat's claw and evening primrose oil were found to significantly increase the levels of antiretrovirals and patients should be monitored for adverse effects while taking these dietary supplements.
Uncaria tomentosa (cat's claw) improves quality of life in patients with advanced solid tumors
de Paula LC, Fonseca F, Perazzo F +2 more
Treatment improved the patients' overall quality of life.
DNA repair enhancement of aqueous extracts of Uncaria tomentosa in a human volunteer study
Sheng Y, Li L, Holmgren K +1 more
There was a statistically significant decrease of DNA damage and a concomitant increase of DNA repair in the supplement groups (250 and 350 mg/day) when compared with non-supplemented controls (p < 0.05).
Persistent response to pneumococcal vaccine in individuals supplemented with a novel water soluble extract of Uncaria tomentosa, C-Med-100
Lamm S, Sheng Y, Pero RW
Statistically significant immune enhancement for the individuals on C-Med-100 supplement was observed by (i) an elevation in the lymphocyte/neutrophil ratios of peripheral blood and (ii) a reduced decay in the 12 serotype antibody titer responses to pneumococcal vaccination at 5 months.
Safety Information
Potential Side Effects
Generally well tolerated; occasional headache, dizziness or GI upset. Rare reports of acute kidney injury in susceptible people.
Contraindications
Organ transplant; autoimmune disease on immunosuppressive therapy; pregnancy.
Drug Interactions
- Immunosuppressants including ciclosporin and tacrolimus
- CYP3A4 substrates (inhibition reported)
- Antihypertensives (additive BP lowering)
- Anticoagulants and antiplatelets
Pregnancy & Breastfeeding
Pregnancy: likely_unsafe
Breastfeeding: likely_unsafe
Dosage Guidelines
Dosage Used in Studies
100-350 mg
Best Time to Take
Daily with food
Best Form
POA-standardised, TOA-free bark extract
Forms Compared
Used in the osteoarthritis trial at 100 mg/day
Used in the rheumatoid arthritis trial; specify TOA-free
Traditional; alkaloid content unpredictable
Food & Timing
With food.
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.