Devil's Claw Overview

Devil's claw is a native of South Africa, so named because of its rather peculiar appearance. Its large tuberous roots are used medicinally, after being chopped up and dried in the sun for 3 days.

Native South Africans used the herb to reduce pain and fever and stimulate digestion. European colonists brought devil's claw back home, where it became a popular treatment for arthritis.

The evidence for devil's claw is fairly preliminary, with the largest and most well-designed studies showing marginal benefits at best. Most studies have evaluated it for treatment of arthritis.

A double-blind study compared devil's claw to the European drug diacerhein. ¹ Diacerhein is a member of a drug category not recognized in the United States: the so-called "slow-acting drugs for osteoarthritis" (SADOAs). Unlike anti-inflammatory drugs such as ibuprofen, SADOAs don't give immediate relief, but rather act over a period of weeks to gradually reduce arthritis pain. The supplements glucosamine and chondroitin have been proposed as natural SADOAs.

In this trial, 122 individuals with osteoarthritis of the hip and/or knee were given either devil's claw or diacerhein for a period of 4 months. The results showed that devil's claw was as effective as diacerhein, as measured by pain levels, mobility, and need for pain-relief medications (such as acetaminophen or ibuprofen). While this might seem impressive, diacerhein itself is only slightly effective, ² and, in such cases, comparative studies must use a placebo group to achieve reliable results.

Another double-blind study followed 89 individuals with rheumatoid arthritis for a 2-month period. The group given devil's claw showed a significant decrease in pain intensity and improved mobility. ³ A third double-blind study of 50 people with various types of arthritis found that 10 days of treatment with devil's claw provided significant pain relief. ⁴ A fourth study compared devil's claw against Vioxx, an anti-inflammatory drug (currently off the market). ⁵ While it was widely reported that devil's claw was equally effective as the drug, in fact, the study was too small to produce statistically meaningful results.

Other studies have evaluated devil's claw for treatment of muscular tension and discomfort. One of these was a 4-week, double-blind, placebo-controlled trial that evaluated 63 patients with muscular tension or pain in the back, shoulder, and neck. ⁶ The results showed significant pain reduction in the treatment group as compared to the placebo group. However, a double-blind study of 197 individuals with back pain found devil's claw marginally effective at best. ⁷ Similarly unimpressive results were seen in a previous double-blind study of 118 people with back pain. ⁸ We don't know how devil's claw might work. Some studies have found an anti-inflammatory effect, but others have not. ⁹ Apparently, the herb doesn't produce the same changes in prostaglandins as standard anti-inflammatory drugs. ¹⁰

A typical dosage of devil's claw is 750 mg 3 times daily of a preparation standardized to contain 3% iridoid glycosides.

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