Cats Claw

Uncaria tomentosa


Cats claw, named for its claw-like thorns, grows wild in many countries throughout Central and South America, especially in the Amazon rainforest. The use of cats claw as a medicine dates back to the Inca civilisation and the plant has been used by subsequent generations to treat pain and wounds, stomach ailments, arthritis and cancer. In Peru, it has been valued for centuries as a contraceptive. Despite its long history as a medical remedy, cats claw has only been studied since the 1970s by Western researchers, whose discoveries confirm that the plant may indeed be a useful immune booster and cancer fighter. Cats claw is harvested primarily in the wild.

Parts used

The inner bark or roots of cats claw are used to make capsules, tablets, teas and liquid extracts.


The main active ingredients in cats claw are procyanidolic oligomers (PCOs), which have been shown to inhibit tumour growth in animals. In the 1980s, German researchers identified other compounds that appear to stimulate immune cells called phagocytes, which destroy certain disease-causing micro-organisms. An Italian study in the early 1990s detected the presence of quinovic acid glycosides, compounds that are thought to act as anti-oxidants, ridding the body of damaging free radicals. Cats claw also contains alkaloids such as rhynchophylline, which helps to prevent blood clots in blood vessels, dilate peripheral blood vessels, lower the heart rate and reduce cholesterol. Small studies in humans have shown a possible benefit of cats claw in osteoarthritis and rheumatoid arthritis, but no wider-ranging trials have been done.

Medicinal uses

Cats claw is prescribed mainly to regulate the immune system and in Germany and Austria, where it is considered to be a potent medicine, it is dispensed only with a doctor’s prescription. Cats claw is being studied for a number of other possible uses, including Crohn’s disease, multiple sclerosis, systemic lupus erythematosus (SLE or lupus), endometriosis and kidney problems and Alzheimer’s disease. Although further research is needed to confirm the full benefits of cats claw, it is recommended by naturopathic practitioners to:

  • Strengthen the immune system.
  • Help fight conditions such as cancer, herpes, AIDS, asthma, chronic fatigue syndrome, diabetes, circulatory problems and arthritis.
  • May help in the treatment of a variety of conditions, such as Alzheimer’s disease and lupus.


Talk to your medical practitioner before taking any herbal supplements.
Few side effects have been reported by patients taking recommended dosages of cats claw, although headaches, dizziness, nausea and vomiting have been experienced. If you are pregnant or trying to become pregnant, have a condition that affects the immune system, are taking medications to thin the blood, treat irregular heartbeat or lower blood pressure, or are about to undergo surgery, avoid using cats claw. Always consult your medical practitioner before embarking on a course of natural remedies.

Domestic & culinary uses

No documented uses of cats claw as a food ingredient were found.


Cats claw grows wild in many countries throughout Central and South America, especially in the Amazon rainforest, where it is harvested. It is not recommended as a plant for domestic growth.

Photo credits

  1. Photo by Vangeliq.petrova (петрова) [GFDL or CC-BY-SA-3.0-2.5-2.0-1.0], via Wikimedia Commons
Information in our herb library is intended only as a general reference for further exploration. It is not a replacement for professional health advice and does not provide complete dosage information, format recommendations, toxicity levels, or possible interactions with prescription medicines. Accordingly, this information should only be used under the direct supervision of a suitably qualified health practitioner such as a registered homeopath, naturopath or phytotherapist.