An African herb traditionally used to treat inflammation shows promise as a safe and effective treatment for osteoarthritis. In a new double-blind clinical study, devil’s claw extract (Harpagophytum procumbens) was as effective as the arthritis drug diacerhein in relieving the pain and stiffness of osteoarthritis, with far fewer side effects than the drug.
Devil’s claw, which gets its common name from its sharp, hooklike fruits, is taken as a tea in Africa for pain, inflammation, indigestion, and fever, and used externally as a remedy for skin problems such as boils and ulcers. Today in Europe, devil’s claw root extract is a popular treatment for arthritic complaints, and at least ten modern clinical studies support the herb’s effectiveness in relieving lower-back or arthritis pain. Some of the studies also suggest that it may help with the stiffness and loss of function that typically accompanies osteoarthritis.
In the most recent study, researchers compared the effects of devil’s claw extract with diacerhein, a new, slow-acting type of arthritis drug. The study participants were 122 people with active osteoarthritis of the knee or hip who were randomly assigned to treatment with either six 435-mg devil’s claw capsules plus 2 placebo capsules daily or two 50-mg capsules of diacerhein plus 6 placebo capsules daily for four months. The participants were allowed to take additional analgesics for “rescue pain relief” if their study treatment provided inadequate relief.
Results showed that devil’s claw and diacerhein were equally effective in relieving pain and improving function over the course of the study, but by the end of the four-month treatment, people in the devil’s claw group were taking significantly fewer “rescue” pain relievers. Equally important, the devil’s claw treatment proved safer than diacerhein. The most common side effect in the study was diarrhea, reported by 26.7 percent of the people taking the drug, compared with 8.1 percent of those taking devil’s claw.
The devil’s claw extract used in the study was a French product marketed under the trade name Harpadol. Devil’s claw extracts are often standardized to the compound harpagoside, but studies suggest that other compounds in the root also contribute to its pain-relieving activity.
Evelyn Leigh is a writer, editor and herbalist who lives to garden in Boulder, Colorado. She is the co-author of the Herb Research Foundation’s science-based book, The Encyclopedia of Popular Herbs (Prima Publishing, 2000).
Chantre, P., et al. “Efficacy and tolerability of Harpagophytum procumbens versus diacerhein in treatment of osteoarthritis.” Phytomedicine 2000: 7(3): 177–183.