Cat's Claw (Uncaria tomentosa, Uncaria guianesis)

Cat's Claw (Uncaria tomentosa, Uncaria guianesis)

PEP Topic 

Cat's claw is a wood vine that grows wild in central and South America, particularly in the Amazon rainforest. Historically, cat's claw has been used to prevent and treat disease dating back to the Inca civilization. Its inner bark is used to make liquids, capsules, and teas, and preparations can be applied to the skin. Cat's claw may have some properties to boost the immune system and reduce inflammation. Cat's claw has been examined for its effects on sleep-wake disturbances, fatigue, anxiety, and depression in patients with cancer.

Effectiveness Not Established

Research Evidence Summaries

de Paula, L.C.L., Fonseca, F., Perazzo, F., Cruz, F.M., Cubero, D., Trufelli, D.C., . . . del Giglio, A. (2015). Uncaria tomentosa (cat's claw) improves quality of life in patients with advanced solid tumors. Journal of Alternative and Complementary Medicine, 21, 22–30.

doi: 10.1089/acm.2014.0127

Study Purpose:

To assess the efficacy of Uncaria tomentosa (cat’s claw) on quality of life, fatigue, anxiety, depression, and sleep quality in patients with terminal cancer when used in conjunction with monitoring for changes in biochemical and inflammatory parameters

Intervention Characteristics/Basic Study Process:

A 100 mg dose of dry extract of Uncaria tomentosa (U tomentosa) was administered orally three times daily for eight weeks.

Sample Characteristics:

  • N = 51  
  • MEDIAN AGE = 64 years (range = 33–85 years)
  • MALES: 53%, FEMALES: 47%
  • KEY DISEASE CHARACTERISTICS: Solid tumors with no additional therapeutic options; life expectancy greater than two months
  • OTHER KEY SAMPLE CHARACTERISTICS: 74.5% white; 19.6% colon; 15.3% breast, 13.7% lung; Karnofsky Performance Status ≤ 80 (65%)


  • SITE: Single-site 
  • SETTING TYPE: Not specified
  • LOCATION: Academic center, Sao Paulo, Brazil

Phase of Care and Clinical Applications:

  • PHASE OF CARE: End-of-life care
  • APPLICATIONS: Palliative care

Study Design:

  • Single-center, open-label study
  • Prospective, repeated measures

Measurement Instruments/Methods:

  • European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ C30)
  • Functional Assessment of Chronic Illness Therapy–​Fatigue (FACIT-F)
  • Chalder Fatigue Scale (CFQ)
  • Hospital Anxiety and Depression Scale (HADS) 
  • Pittsburgh Sleep Quality Index–Brazil (PSQI-BR)


Overall quality of life (p = 0.00411) and social functioning (p = 0.0341) improved. Fatigue as assessed by the CFQ improved (p = 0.0496). No improvement in sleep quality anxiety was determined. There was no change in liver function, kidney function, blood counts, or inflammatory blood parameters.


Managing symptoms in patients with no additional treatment options is important. U tomentosa improved overall quality of life and social functioning and reduced fatigue in patients with cancer who had no additional treatment options. U tomentosa did not affect sleep quality, anxiety, or depression, but it did not alter the inflammatory parameters studied.


  • Small sample (< 100)
  • Risk of bias (no control group)  
  • Risk of bias (no blinding)
  • Risk of bias (sample characteristics)
  • Findings not generalizable


Nursing Implications:

U tomentosa may be useful in reducing fatigue and improving overall quality of life in patients who have no other treatment options.