Dr Clare Materia Medica

The botanical name Harpagophytum means ‘hook plant’ in Greek, it is named after the hook-covered fruits of the plant. Devil’s claw is native to southern Africa and has been used traditionally as a bitter tonic for digestive disturbances, febrile illnesses, allergic reactions and to relieve pain. 

Also known as: Grapple Plant.

Scientific name: Harpagophytum procumbens.

Botanical Family: Pedaliaceae.

Part used: The tubers which are underground stems. 

Traditional use.

Devil's claw is traditionally used for arteriosclerosis, osteoarthritis, rheumatoid arthritis, gout, muscle soreness, fibrositis, lumbago, tendonitis, pleuritic chest pain, gastrointestinal upset or dyspepsia, fever, migraine headache, menstrual problems, allergic reactions, loss of appetite, kidney and bladder disease, and degenerative disorders of the locomotor system.

Safety.

No concerns regarding safety when used orally and appropriately. Devil's claw seems to be well-tolerated when used daily for up to a year.^(1,2,3,4,5) 

Pregnancy: Consult a medical herbalist.

Breastfeeding: Consult a medical herbalist.

Constituents

Iridoid glycosides principally harpagoside

Sugars.

Triterpenes.

Phytosterols especially beta sitosterol.

Aromatic acids.

Flavonoids; kaemferol and lutein.

Harpagoquinone 

Scientific evidence.

Back pain. Taking devil's claw orally seems to lessen nonspecific low-back pain. Some evidence suggests that an aqueous extract of devil's claw at doses of 50-100mg harpagoside daily has an anti-inflammatory effect equal to 13.5mg rofecoxib (Vioxx).^(2,3,5)  

If the resources put into even the marketing budget of Vioxx was spent investigating this herb the tragedy of the Vioxx deaths and ilness may not have happened.

Osteoarthritis. Taking devil's claw orally alone or in conjunction with nonsteroidal anti-inflammatory drugs (NSAIDs) helps decrease osteoarthritis-related pain.^(1,2,3,4,13) Evidence shows that devil's claw is comparable to diacerhein (a slow-acting drug for osteoarthritis; not available in the US) for improving osteoarthritis pain in the hip and knee after 16 weeks of treatment. Patients taking devil's claw have been able able to decrease the use of NSAIDs for pain relief.⁽¹⁾ This study used a specific powdered devil's claw root product (Harpadol, Arkopharma) containing 2% of the constituent harpagoside (9.5mg/capsule) and 3% total iridoid glycosides (14.5mg per capsule).⁽¹⁾ Another specific devil's claw extract (Doloteffin, Ardeypharm) 2400mg/day providing 60mg/day of the harpagoside constituent has also been researched.^(2,4)

Rheumatoid arthritis (RA). Preliminary evidence suggests that taking devil's claw extract orally might not be helpful for RA.⁽⁶⁾ More evidence is needed to rate devil's claw for this use.

Mechanism of action.

Devil's claw contains iridoid glycoside constituents primarily harpagoside but it appears that other compounds besides harpagoside contribute to its effect.^(7,8) It also contains the phenylethanol derivatives and an oligosaccharide.⁽⁸⁾ People use devil's claw for osteoarthritis and other inflammatory conditions because the iridoid glycoside constituents seem to have an anti-inflammatory effect.⁽¹⁾ Some preliminary research suggests that harpagoside inhibits both the cyclooxygenase (COX) and lipoxygenase inflammatory pathways.⁽⁹⁾ Devil's claw seems to inhibit COX-2 (but not COX-1) and nitric oxide synthetase, a modulator of inflammation.⁽¹⁰⁾ Some evidence suggests that the anti-inflammatory effect is due to increased synthesis and release of tumor necrosis factor by compounds other than harpagoside.⁽⁸⁾ However, research in humans shows no effect of devil's claw on the arachidonic acid pathway.⁽¹¹⁾

Adverse reactions.

Devil's claw is generally well tolerated. A small percentage of patients complain of gastrointestinal upset. This can only be determined by trying the herb. It is more likely in patients wih peptic ulceration. In general if you have digestive problems start with a lower than usual dose and increase the dose slowly to test your tolerance level.

Devil's claw can cause allergic skin reactions following oral treatment.                                                                                                                                                                                                                                                                                                         

Although references cite that devil’s claw may lower blood sugar levels, upset gallstones and may affect blood pressure, these are extrapolations from physiological effects or animal studies and I can find no clinical studies or even case reports of problems. Be aware that herbs alter physiology and monitor any chronic condition for change when you use herbs.

Interactions with herbs and supplements.

None known.

Interactions with drugs.

Warfarin (Coumadin) an anti blood clotting agent.

Interactions with foods.

None known. 

Interactions with laboratory tests.

None known.

Interactions with diseases or conditions.

Peptic Ulcer Disease: May cause gastrointestinal upset.¹²

However lower doses may be clinically indicated and well tolerated for digestive discomfort

Dosage.

Recommended dose: 6-12mls per day 1:5 tincture 25% alcohol.

Liquid extract: 1-2mls 1:1 25% alchohol.

Decoction: range from 2-4 tsps. per day.

Powder/capsule: 1,500mgs per day, 

The recommended dose of Dr Clare’s Joint Support Blend provides 3mls per day of 1:3 Tincture.

This is when taken at a dose of 5mls three times a day. This is equivalent 750mgs per day.

 References.

1.   Chantre P, Cappelaere A, Leblan D, et al. Efficacy and tolerance or Harpagophytum procumbens versus diacerhein in treatment of osteoarthritis. Phytomedicine 2000;7:177-84.

2.   Chrubasik S, Thanner J, Kunzel O, et al. Comparison of outcome measures during treatment with the proprietary Harpagophytum extract doloteffin in patients with pain in the lower back, knee or hip. Phytomedicine 2002;9:181-94.

3.   Gagnier JJ, Chrubasik S, Manheimer E. Harpgophytum procumbens for osteoarthritis and low back pain: a systematic review. BMC Complement Altern Med 2004;14:13.

4.   Wegener T, Lupke NP. Treatment of patients with arthrosis of hip or knee with an aqueous extract of devil's claw (Harpagophytum procumbens DC). Phytother Res 2003;17:1165-72.

5.   Chrubasik S, Kunzel O, Thanner J, et al. A 1-year follow-up after a pilot study with Doloteffin for low back pain. Phytomedicine 2005;13:1-9.

6.   Grahame R, Robinson BV. Devils's claw (Harpagophytum procumbens): pharmacological and clinical studies. Ann Rheum Dis 1981;40:632.

7.   Lanhers MC, Fleurentin J, Mortier F, et al. Anti-inflammatory and analgesic effects of an aqueous extract of Harpagophytum procumbens. Planta Med 1992;58:117-23 .

8.   Fiebich BL, Heinrich M, Hiller KO, Kammerer N. Inhibition of TNF-alpha synthesis in LPS-stimulated primary human monocytes by Harpagophytum extract SteiHap 69. Phytomedicine 2001;8:28-30..

9.   Chrubasik S, Sporer F, Dillmann-Marschner R, et al. Physicochemical properties of harpagoside and its in vitro release from Harpagophytum procumbens extract tablets. Phytomedicine 2000;6:469-73.

10.  Jang MH, Lim S, Han SM, et al. Harpagophytum procumbens suppresses lipopolysaccharide-stimulated expressions of cyclooxygenase-2 and inducible nitric oxide synthase in fibroblast cell line L929. J Pharmacol Sci 2003;93:367-71.

11.  Moussard C, Alber D, Toubin MM, et al. A drug used in traditional medicine, harpagophytum procumbens: no evidence for NSAID-like effect on whole blood eicosanoid production in human. Prostaglandins Leukot Essent Fatty Acids. 1992;46:283-6.

12.  Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

13. Effectiveness and safety of Devil's Claw tablets in patients with general rheumatic disorders. Phytotherapy Research

Volume 21, Issue 12, pages 1228–1233, December 2007