← All supplements

Cat's claw

Supplement botanical immunebone & joint
Aka: Uncaria tomentosa, una de gato
Brands seen in Singapore: NOW Foods, Swanson Vitamins, Nature's Answer, Solaray, Nature's Way
Not medical advice. Check with your doctor or pharmacist before you start, stop or change the timing of anything you take.
How to use
What it’s for
Promoted for joint problems — no conclusive evidence
Pros & cons
Pros
  • NCCIH: appears safe orally for up to 6 months
  • Centuries of traditional amazonian use
Cons
  • No conclusive evidence for any health purpose
  • Very few high-quality human trials exist
  • May slow clotting — bleeding risk at surgery
Sources
  1. NIH NCCIH — Cat's Claw, Background · read 2026-08-27
    what it says
    “Indigenous people of the Amazon rainforest have used cat's claw for centuries to ward off disease. Today, cat's claw is promoted for osteoarthritis, rheumatoid arthritis, cancer, viral infections, and other conditions.”
  2. NIH NCCIH — Cat's Claw, What Have We Learned · read 2026-08-27
    what it says
    “There's no conclusive scientific evidence based on studies in people that supports using cat's claw for any health purpose, including COVID-19 … many of the studies did not use rigorous methods”
  3. NIH NCCIH — Cat's Claw, How Much Do We Know · read 2026-08-27
    what it says
    “There have been very few high-quality clinical trials (studies done in people) of cat's claw.”
  4. NIH NCCIH — Cat's Claw, What Do We Know About Safety (duration, topical use) · read 2026-08-27
    what it says
    “Cat's claw appears to be safe when used orally for short periods of time, as much as 6 months. However, there is insufficient reliable information about its safety when applied to the skin.”
  5. NIH NCCIH — Cat's Claw, What Do We Know About Safety (immune activity and clotting) · read 2026-08-27
    what it says
    “Cat's claw might make the immune system more active, which could increase symptoms of autoimmune diseases … Cat's claw may slow blood clotting, and this might increase the risk of bleeding during surgery.”
  6. NIH NCCIH — Cat's Claw, What Do We Know About Safety (drug interactions) · read 2026-08-27
    what it says
    “There are theoretical reasons to suspect that cat's claw might interact with anticoagulant, antiplatelet, and blood pressure drugs, and other supplements as well.”
  7. NIH NCCIH — Cat's Claw, What Do We Know About Safety (pregnancy and breastfeeding) · read 2026-08-27
    what it says
    “Some studies of the use of cat's claw during pregnancy suggest it is unsafe. Little is known about whether it's safe to use cat's claw while breastfeeding.”
  8. HSA Singapore — Guidelines on Prohibited and Restricted Ingredients in Health Supplements and Traditional Medicines, GL-CHPB-1-012 Rev. No. 001 (October 2025), Annex A (118 rows) and Annex B (4 rows) — cat's claw / Uncaria tomentosa not listed in either (alphabetical neighbours 103. Symphytum asperum, 104. Urginea maritima) · read 2026-08-27
    what it says
    “The objective of this guideline is to highlight the substances of concern when used in HS and TM and is not meant to be an exhaustive list.”
  9. HSA Singapore — Health Supplements Guidelines GL-CHPB-3-001 Rev. No. 020 (January 2026), clause 4.8 with Tables 4–5 (vitamins and minerals only — no botanical rows) · read 2026-08-27
    what it says
    “4.8 HS for use by the general adult population should not contain vitamins and minerals exceeding the stipulated limits stated in Tables 4 and 5.”
  10. iHerb Singapore — Cat's Claw category page, default listing order · read 2026-08-27
    what it says
    “1 - 19 of 19 results: NOW Foods, Cat's Claw, 500 mg; Swanson Vitamins, Full Spectrum Cat's Claw; Nature's Answer, Cat's Claw Bark; Solaray, True Herbs, Cat's Claw; Nature's Way, Cat's Claw Bark”
Report a correction View as JSON

Updated 2026-08-29. Every line above traces to a numbered source. Kozen-X is not a medical device and does not give medical advice. It lists what published sources have written down — nothing more. A pair not listed is unrecorded, not cleared. Before you start, stop or re-time anything, talk to your doctor or pharmacist.