Harpagophytum: Devils claw research
by Paul Bergner
Medical Herbalism 5(1):9
Research in a recent article in Planta Medica evaluated the anti-inflammatory and analgesic properties of Devil’s Claw (Harpagophytum procumbens) in a series of animal experiments. The research confirmed the use of Devil’s Claw for headaches, allergic reactions, and rheumatism, but its immediate clinical implications are not clear.
The results of previous studies of Devil’s Claw for subacute inflammation have been mixed, but past tests in acute inflammation have all given negative results. This study found an aqueous extract effective in acute inflammation, but used intraperitoneal injection rather than the oral route used in previous studies. Some previous studies have been flawed by not carefully controlling the form of Devil’s Claw being used. This study properly used only the secondary roots, and used chromatography to verify the presence of marker active constituents.
This study demonstrated that the supposed “active ingredient” harpagoside was not involved in the acute anti-inflammatory effect, and only partially contributed to the analgesic effect, demonstrating that the action of Devils claw, like that of most herbs, comes from the combined effects of many constituents.
A Devil’s Claw infusion is used traditionally in southern Africa for indigestion, fevers, blood disorders, and as a bitter tonic. The dried tuber is given to pregnant women for pain three times daily in doses of 0.25g (stage of pregnancy not stated). The fresh tuber is used to make an ointment for ulcers, boils, and skin lesions. Other extracts (type not named) are used for rheumatic diseases, allergic reactions, headache and other pain. There are no reports on side effects, but it is known not to be outright poisonous (Watt). It was introduced into Europe through Germany in the early 20th century, and is used there primarily for its anti-inflammatory effects, but also for diseases of the gall bladder, liver, kidney, and bladder, for allergies, hardening of the arteries, lumbago, heartburn, and nicotine poisoning (Kämpf).
Weiss suggests use of Devil’s Claw in dyspepsia and gall bladder disease, but cautions that it is contraindicated in stomach ulcers (because of its bitter properties.) He says the plant has approximately the same degree of bitterness as gentian. He also mentions use as an anti-rheumatic, including injection of proprietary preparations directly into inflamed joints. He cites German research showing that it lowers cholesterol and “neutral fat” levels, and suggested it could be especially beneficial for older patients the rheumatic complaints, obesity, and hyperlipidemia. Weiss also expressed skepticism about the quality of the plant available in commercial preparations, due to possible adulteration of the secondary roots with primary roots.
The British Herbal Pharmacopoeia (1982) suggests three-times-a-day doses of 0.1-.25g dried tuber or 0.5-1ml of 1:5 tincture in 25% alcohol.
Kämpf, R. 1976 Harpagophytum procumbens DC. Teufelskralle. Schweiz Apoth.-Ztg.
Watt JM, Breyer-Brandwijk MG, 1962.
The Medicinal and Poisonous Plants of Southern and Eastern Africa. E.
and S. Livingstone, Ltd. London, p. 830.