Patients with osteoarthritis who routinely turn to devil’s claw, Indian frankincense, ginger, and other herbal medicines for symptom relief may want to think twice about this practice.
According to a review of these products that appears in the January 2012 issue of Drug and Therapeutics Bulletin, a publication of the London-based BMJ Group, there is little conclusive evidence to justify their widespread use by patients with the disease (DTB 2012: 50:8-12). A press release about the review points out that few robust studies on the use of herbal medicines for osteoarthritis have been carried out. “And those that have frequently contain design flaws and limitations, such as variations in the chemical make-up of the same herb, all of which comprise the validity of the findings.”
Herbal medicines commonly used to treat osteoarthritis includes vegetable extracts of avocado or soybean oils (ASUs), cat’s claw, devil’s claw, Indian frankincense, ginger, rosehip, turmeric and willow bark. According to the review, the best available clinical evidence suggests that ASUs, Indian frankincense, and rosehip may work, “but more robust data are needed.”
Some herbal medicines may cause adverse reactions in patients taking other medicines and prescription drugs. For example, chronic use of nettle can interfere with drugs used to treat diabetes, lower blood pressure, and depress the central nervous system while willow bark can cause digestive symptoms and renal problems.
The review characterized the use of herbal medicines for osteoarthritis as “generally under-researched, and information on potentially significant herb-drug interactions is limited.”
Although the UK Medicines and Healthcare products Regulatory Agency has approved Traditional Herbal Registrations for several herbal medicinal products containing devil’s claw for rheumatic symptoms, “the trial results for this herb are equivocal,” the review states. “There is little conclusive evidence of benefit from other herbs commonly used for symptoms of osteoarthritis, such as cat’s claw, ginger, nettle, turmeric and willow bark. Healthcare professionals should routinely ask patients with osteoarthritis if they are taking any herbal products.”
The review did not include data on glucosamine and chondroitin sulfate.
— Doug Brunk (on Twitter@dougbrunk)
Photo courtesy anolobb’s photostream