Cat's Claw
Useful mainly for people with osteoarthritis or rheumatoid arthritis seeking an adjunct for joint discomfort.
Quick decision guide
May help most
People with osteoarthritis or rheumatoid arthritis seeking an adjunct for joint discomfort
Common dosing range
100–300 mg/day of standardized extract
When to expect effects
Weeks (4–8)
Watch out for
May stimulate the immune system; avoid with autoimmune disease or immunosuppressants
What is it
Cat's claw (Uncaria tomentosa or Uncaria guianensis), also called uña de gato, is a tropical vine native to the Amazon rainforest. Its inner bark and root have been used in traditional South American medicine for inflammation, immune support, and digestive issues. It is one of the more commonly used Amazonian medicinal plants in Western herbalism.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
osteoarthritis Limited Evidence | Modest | Adults with knee or hand osteoarthritis pain | Weeks |
rheumatoid arthritis adjunct Limited Evidence | Modest | People with RA using it alongside standard therapy | Weeks |
immune support Mixed Evidence | Marker-level changes | Generally healthy adults exploring immune modulation | Weeks |
osteoarthritis
- Effect
- Modest
- Best fit
- Adults with knee or hand osteoarthritis pain
- Time
- Weeks
rheumatoid arthritis adjunct
- Effect
- Modest
- Best fit
- People with RA using it alongside standard therapy
- Time
- Weeks
immune support
- Effect
- Marker-level changes
- Best fit
- Generally healthy adults exploring immune modulation
- Time
- Weeks
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
osteoarthritis
Disease adjunctSmall controlled trials of standardized cat's claw extract report modest reductions in osteoarthritis pain, consistent with its anti-inflammatory actions on NF-kB signaling seen in laboratory work. The trials are few and small, so the size and durability of benefit remain uncertain.
Bottom line: May modestly ease osteoarthritis pain, but evidence is limited and preliminary.
rheumatoid arthritis adjunct
Disease adjunctA small controlled trial in rheumatoid arthritis found modest reductions in the number of tender joints when standardized cat's claw was added to ongoing treatment. Evidence is sparse, and immune-stimulating effects warrant caution in autoimmune disease despite this signal.
Bottom line: Preliminary support as an RA adjunct, but data are thin and immune effects raise caution.
Evidence is mixed
Cat's claw is generally avoided in autoimmune disease for its immune-stimulating effects, yet limited RA trials suggest possible benefit; the balance is unsettled.
immune support
Mechanism onlyCat's claw alkaloids modulate cytokine production and immune-cell activity in laboratory and small human studies, with some work suggesting effects on DNA repair. These are marker-level or mechanistic findings and do not demonstrate fewer infections or other clinical immune benefits.
Bottom line: Immune effects are mechanistic and unproven at the clinical level.
How it works
How to take it
What to track
4 commercial forms
Compare the main delivery options and what they’re best suited for.
Standardized pentacyclic alkaloid extract
Modern supplement form. Pentacyclic chemotype is preferred for immune applications.
Standardized to pentacyclic oxindole alkaloid content
AC-11 (branded extract)
Patented extract used in research, particularly for immune and DNA repair applications.
Standardized hot-water extract
Dried inner bark
Used in traditional South American preparations and modern capsules.
Traditional whole-bark form
Liquid extract / tincture
Common in herbalist combination formulas.
Alcohol-based extraction
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Serious risks
Rare acute kidney injury
Low blood pressure
Who should avoid it
- People with autoimmune disease
- Organ transplant recipients or those on immunosuppressants
- Pregnant or breastfeeding people
- Those with bleeding disorders or upcoming surgery
Pregnancy & breastfeeding
Avoid in pregnancy and breastfeeding due to possible uterine effects and insufficient data.
Interactions
Immune-stimulating effects may reduce drug effectiveness
May potentiate blood-pressure lowering
May affect platelet function and bleeding risk
May alter metabolism of affected medications
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
Frequently asked questions
Where does cat's claw get its name?⌄
The vine has thorns shaped like cat's claws, which it uses to climb trees in the rainforest. The Spanish name 'uña de gato' translates directly to 'cat's claw'.
What's the difference between pentacyclic and tetracyclic cat's claw?⌄
These are two chemotypes of Uncaria tomentosa with different oxindole alkaloid profiles. Pentacyclic is preferred for immune-modulating applications; tetracyclic may have competing CNS effects. Choose products specifying pentacyclic for most uses.
Can cat's claw help my arthritis?⌄
Small trials suggest modest benefit for osteoarthritis pain and function. Effects emerge over 4 to 8 weeks. It is not a substitute for evaluated arthritis treatment in moderate to severe disease.
Is cat's claw safe with autoimmune disease?⌄
Generally avoid in most autoimmune conditions due to immune-stimulating effects. Some practitioners use it in rheumatoid arthritis specifically, but discuss with a clinician familiar with herbal medicine.
Can I take cat's claw with my arthritis medication?⌄
Discuss with your prescriber. Cat's claw may affect immune-modulating medications and could potentially reduce effectiveness of immunosuppressants used in some forms of arthritis.
References by claim
Track Cat's Claw with Pilora
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Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.