Quick Summary

Cat’s Claw (Uncaria tomentosa) is a traditional Amazonian medicinal plant noted for its anti-inflammatory and immunomodulatory activities in preclinical animal studies. Traditionally used for inflammatory conditions, it has been shown to reduce certain cytokines and transcription factors in vivo. Some laboratory (in vitro) studies indicate antimicrobial activity against Borrelia burgdorferi, the pathogen responsible for Lyme disease. However, clinical evidence regarding its effectiveness in humans is limited and inconclusive, with generally low-quality data. Safety data in humans indicate low toxicity, but detailed information on drug interactions and comprehensive safety profiles remains insufficient. Further rigorous clinical trials are needed to clarify its therapeutic potential and safety.

What is it

Cat’s Claw is a woody vine native to the Amazon rainforest. Its Latin name is Uncaria tomentosa. The plant contains various bioactive compounds that have been investigated for their medicinal properties. It has a history of traditional use by indigenous peoples in South America, primarily for inflammatory and immune-related health concerns.

Traditional Uses

  • Used traditionally for inflammatory diseases
  • Applied to support immune function
  • Included in Traditional Chinese Medicine for neuroprotective effects and managing non-motor symptoms of Parkinson’s disease
  • Used in some natural remedies for infections and oral conditions such as denture stomatitis

Active Compounds

The key active compounds in Cat’s Claw are believed to include alkaloids, flavonoids, and other phytochemicals that may exert anti-inflammatory, immunomodulatory, and antimicrobial effects. Specific constituents have been studied for their ability to reduce inflammatory mediators and support cellular immune responses in preclinical models.

Potential Benefits with Evidence Levels

  • Anti-inflammatory and immunomodulatory effects: Supported by preclinical animal studies showing reduction of inflammatory mediators such as IL-6 and NF-kappa-B. (Arado et al., 2024)
  • Antimicrobial activity against Borrelia burgdorferi: Demonstrated in vitro against stationary phase cultures relevant to Lyme disease; no clinical confirmation yet. (Feng et al., 2020)
  • Use in denture stomatitis: Limited clinical evidence suggests potential efficacy and safety comparable to standard antifungals, though current studies have high risk of bias. (Inácio Silveira et al., 2023)
  • Neuroprotective uses in Parkinson’s disease: Traditional use and observational data indicate neuroprotective properties; clinical validation is lacking. (Lin et al., 2020)
  • Potential roles in cancer-related fatigue and breast cancer symptom management: Low to very low certainty evidence, mainly from preclinical sources; clinical trials show methodological limitations. (Matsas et al., 2026; Lopes et al., 2017)

Side Effects

Available data do not consistently report severe or serious adverse effects directly linked to Cat’s Claw. However, incomplete safety reporting and variability in product formulations limit comprehensive safety conclusions. Preclinical studies suggest low toxicity for aqueous and hydroethanolic extracts. (Liang et al., 2025)

Drug Interactions

There is a potential for drug interactions due to Cat’s Claw’s immunomodulatory properties and pharmacokinetic considerations. While direct evidence specific to Cat’s Claw is lacking, caution is advised, especially when taken with anticoagulants or immunosuppressant medications. (Tsai et al., 2013)

Who Should Avoid It

  • Pregnant or breastfeeding women, due to lack of safety data
  • Individuals taking anticoagulants or immunosuppressive drugs, unless supervised by a healthcare provider
  • People with known allergies to plants in the Rubiaceae family may exercise caution
  • Those seeking treatments with strong clinical evidence should consider the limited and low-quality evidence for Cat’s Claw

Evidence Limitations

  • Most evidence comes from preclinical animal or in vitro studies with very limited well-designed human clinical trials
  • Human studies often show high risk of bias and unclear methodological quality
  • Variability in Cat’s Claw product formulations and inconsistent standardization complicate comparisons and reproducibility
  • Lack of robust safety and pharmacokinetic data in humans
  • Clinical trial data on effects in conditions such as cancer-related fatigue, Lyme disease, and denture stomatitis are limited and inconclusive
  • Pharmacovigilance data have incomplete causality assessments, limiting definitive safety conclusions

References

Last Reviewed

April 2024

Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice. Always consult a healthcare provider before starting any new herbal product, especially if you are pregnant, breastfeeding, have existing health conditions, or are taking medications.