Uncaria tomentosa · herb
Evidence tier: insufficient
Anti inflammatory and immune modulating herb that supports joint pain relief and long term immune health through oxindole alkaloids
The oxindole alkaloids in the root and stem bark, mitraphylline among them, are reported in laboratory work to interfere with NF kB signalling and to reduce inflammatory messengers such as TNF alpha, and separately to stimulate immune cells including phagocytes and T helper cells. This is the standard immunomodulatory account and it is drawn from cell and animal studies. It has not been shown to be the operating mechanism in people at the doses they take, and note that immune STIMULATION is a double edged mechanism, not an automatic good.
Insufficient. Both named authorities say the same thing in almost the same words. NCCIH states that there have been very few high quality clinical trials of cat's claw and that there is NO CONCLUSIVE scientific evidence, based on studies in people, supporting the use of cat's claw for ANY health purpose. Memorial Sloan Kettering's About Herbs reaches the same verdict: human data remain insufficient for clinical recommendations. What human data exist are a handful of small studies. A small randomised double blind trial of a pentacyclic alkaloid rich extract in active rheumatoid arthritis reported modest benefit and MSK's own read is that it needs larger, well designed studies to confirm. There are small studies in cancer patients reporting reduced chemotherapy side effects and improved quality of life, which is a disease population under oncology care and cannot support a consumer immune or joint claim. The traditional Amazonian use is genuine and well documented, and the immunomodulatory laboratory work is real. Neither is clinical evidence. MSK also records a preclinical signal that deserves stating: cat's claw could stimulate the survival of paediatric leukaemic cells, which is a reason for caution rather than a reason to sell it as an immune booster.
NIH LiverTox records supplement practice as 30 to 300 mg of extract once daily. Doses vary widely by preparation and no dose has been clinically validated for any indication.
Take 300 to 500mg of standardised extract daily with food. Allow 4 to 6 weeks for anti inflammatory effects to build. Use standardised preparations, root bark extract is the most studied form.
Avoid in pregnancy, traditional use as a contraceptive and abortifacient. Avoid in breastfeeding. Not for use in children under 3. May interact with anticoagulants and immunosuppressants.
Pregnancy: avoid
Breastfeeding: avoid
Active compounds: pentacyclic oxindole alkaloids, mitraphylline, quinovic acid glycosides, flavonols
Remedies using Cat's Claw · Browse by body system · Check it against what you take
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.