Cat's Claw
Uncaria tomentosa
Efficacy
- Indications with possible efficacy:
None - Indications with possible, but poorly documented efficacy :
Osteoarthritis and rheumatoid arthritis (popular use) - Other indications with no proof of efficacy:
Contraception
Diverticulitis
Gastritis
Hemorrhoids
Immune system stimulant
Inflammation
Intestinal inflammatory disease
Peptic ulcers
Security
- Risk of Drug Interactions: Low
- Adverse Effects: Rare
Description
Part of the plant used: root and bark
Cat's claw is indigenous to the Tropics, especially to South-East Asia and South America; it is part of the vine family. Its name comes from the fact that there are small claw-like thorns at the junction of the stem and leaf. It is largely used by South American healers who claim that its potency can restore health. It is believed to have anti-inflammatory, antimutagenic, anticancer and antioxidant properties, however its mechanism of action is unknown. Its activities are linked to the plant's many alkaloids which appear to have varying properties.
Cat's claw is available in tablets or capsules and sometimes in combination with other products.
Direction of use
- Osteoarthritis and rheumatoid arthritis:
Studies on animals and in laboratories have shown anti-inflammatory activity. Dose recommendations vary greatly from one source to another.
Usual doses:
500 to 1000 mg of cat's claw (capsules and tablets contain the raw herb containing 1,3 % of pentacyclic oxindoles), one to three times a day.There is insufficient reliable information to conclude that cat's claw is effective in any other indication.
Precautions
- Side effects
Based on its long history, cat's claw does not appear to be associated with any toxicity. Cat's claw may cause headache, vomiting, hypotension and dizziness. - Contraindications
Avoid its use if autoimmune diseases (multiple sclerosis, systemic lupus erythematosus) because of its immunostimulating properties. - Interactions
Using cat's claw in combination with antihypertensive agents may increase the risk of hypotension. Cat's claw may interfere with immunosuppressant because of its immunostimulating properties. Before taking cat's claw, check with your pharmacist to make sure that there are no interactions with your regular medication. - Pregnancy and breastfeeding
Since there is no safety data available concerning its use during pregnancy and breast-feeding, pregnant and lactating women should not take cat's claw. Because of its potential contraceptive effect, women who wish to become pregnant should discontinue its use.
Clinical notes
- Cat's claw has been used by Peruvian and other South American healers for a very long time. They have used it to treat some types of gastrointestinal problems, tumors, cancer and as a contraceptive. Cat's claw does not appear to be associated with any severe toxicity. Current reliable information leads us to believe that it may be effective in some of its proposed uses, but further research is needed to determine its exact value.
Warning
In 2004, Canada adopted new regulations that control the manufacturing, packaging, labeling and importing of natural health products. The new regulations also include an adverse reaction reporting system. Products that conform to the regulation's criteria are identified with a natural product number (NPN) and can be legally sold in Canada. This number indicates that the product meets specific criteria for safety and purity, not that it is effective for any indication.
Medicinal plant contents vary naturally from plant to plant - just as fruits from the same package may vary in taste and texture. There is no standard to measure the active content of each plant. Thus, efficacy of natural products should be expected to vary from brand to brand as well as from bottle to bottle of the same brand.
For more information about the Natural Health Products Regulations, or to check if a product has been assessed, visit the Health Canada website at www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php.
References
- Natural Medicines Comprehensive Database, Therapeutic Research Faculty, 2010
- Peirce, Andrea. Practical Guide to Natural Medicines, APha, 1999
- Facts & Comparisons, The Lawrence review of natural products, 1998
- Chandler, Frank. Herbs - Everyday Reference for Health Professionals, CphA - CMA, 2000
- Passeportsanté.net. Griffe de chat. www.passeportsante.net
- Barnes J. et Al. Herbal Medicines, 2nd edition, Pharmaceutical Press, 2002
- Rotblatt M. et Ziment I. Evidence-Based Herbal Medicine, Hanley & Belfus, 2002
- Natural Therapeutics Pocket Guide, 2000-2001
- The Review of Natural Products, 6th Edition, 2010
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The patient information leaflets are provided by Vigilance Santé Inc. This content is for information purposes only and does not in any manner whatsoever replace the opinion or advice of your health care professional. Always consult a health care professional before making a decision about your medication or treatment.