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Devil's Claw

Devil's Claw

Botanical Description & Habitat

Harpagophytum procumbens

Family
Pedaliaceae

Common Names
Grapple plant
Wood spider

Habitat
Southern and Eastern Africa

Medicinal Parts
Cut, dried tuber

Historical Properties & Uses

Devil's claw has become a primary treatment for arthritis and rheumatism.

Secondarily, it is often used to treat gastro-intestinal problems, much in same manner our Western bitters are used.

Originally from South Africa, use of the plant has made its way to America via the British isles. It is generally regarded as both safe and effective, and works mainly as an anti-inflammatory agent. In Africa, actually in the Kalahari Desert and Nambian steppes, the root is used as a treatment for indigestion, blood diseases, fever, pain and pregnancy-related problems.

Externally, devil's claw root is made into ointments for skin rashes, wounds and the like. Diabetes, hepatitis, kidney and bladder deficiency, nervous malaise and respiratory ailments are all treated with devil's claw preparations.

Insofar as hardening of the arteries pertains to complications of aging, devil's claw finds application. There is some concern in the industry about the difficulty of obtaining good devil's claw root; only certain portions of the root contain active constituents, and often the whole root is supplied to manufacturers.

To help circumvent this problem, standardized preparations are now being produced. Consumers would be well-advised to ask for the standardized extract.

This herb has approval status by the German Commission E.

This herb has approval status by the German Commission E for loss of appetite (see appetite disorders) and dyspepsia.

It is also supportive for diseases of the locomotor system.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Method of Action

Arthritis and Rheumatism: Anti-inflammatory Effects
Since the end of World War II, devil's claw has been used in medical institutions throughout southern Africa, and in some hospitals and clinics in Germany, as a treatment for inflammatory diseases. Most of these trials have been partially to totally effective. The first published report of this early research appeared in 1958. In that paper, devil's claw was reported to be effective in reducing inflammation and swelling in experimentally-induced arthritis. Using simple water extracts, the researcher was able to reduce swelling from 300-800% in a matter of days.

By 1962, the active component, harpagoside, had been identified, and in 1970 this compound was subjected to a rigorous pharmacological screening trial in which the anti-inflammatory property was validated. Whole devil's claw preparation was found to be superior to pure harpagoside, both were found to be safe; furthermore, the anti-arthritic effect was found to not be due to any pain-killing property of the plant, since it had none. Meanwhile, other reports were appearing reporting good clinical results. In one case, over 100 patients were treated with either pure devil's claw or with a combination of herb and standard treatment. Evidence for lack of toxicity continued to accumulate. Other important chemicals have been identified: harpagide, procumbide, beta-sitosterol, stigmasterol, fatty acids, triterpenes and flavonoids.

An early review paper on devil's claw suggested the plant was a good stimulant of the lymphatic system, with detoxifying effects that extended to the whole organism, and provided evidence from clinical studies involving close to 400 persons. The plant was indeed effective for most of the conditions listed in the folklore section above, especially as pertaining to the liver, gallbladder, bladder and kidneys.

More recent studies have found devil's claw preparations are generally well suited for the treatment of chronic rheumatism, arthritis, gout, spondylosis-induced lower back pain, neuralgia, headaches, and lumbago. One study found its anti-inflammatory effects equaled those of pyrazolone derivatives and the commonly prescribed anti-arthritic phenylbutazone. Analgesic effects of a subjective nature are reported, but objective tests are ambiguous on this point. Relief of pain is probably a side benefit of reduced inflammation. Improved motility in the joints is often reported, as well as improved feeling of well-being. Currently, physicians in Europe are injecting devil's claw extract directly into arthritic joints, where it acts much like cortisone in terms of reducing inflammation. As in the case of most arthritis treatments, not everybody benefits, but there are enough to do to warrant further investigation of this plant, and to recommend it as a possible treatment option.

Not all studies have reported success. For example, in one case, 13 patients exhibiting various kinds of arthritis, for whom conventional therapy had failed, were given devil's claw tablets (410mg/3xdaily for six weeks) without positive results. Simultaneous rat studies likewise produced negative results, even though indomethacin was effective. The lack of toxicity of harpagophytum was again established in these trials. But the lack of positive effect is hard to explain when compared to the many other reports. The use of a highly group of subjects may have contributed to the failure. At any rate, it is obvious that much more experimental and clinical work needs to be done on this plant.

British Pharmacopoeia recognizes devil's claw as having anti-inflammatory, anti-rheumatic, analgesic, sedative and diuretic properties, and as being good for rheumatism, arthritis, gout, mylagia, fibrositis, lumbago, pleurodynia. There are suggestions of combining it with menyanthes, apium, gaultheria and dioscorea in the treatment of rheumatism.

Devil's Club has Good Gastro-intestinal Properties
Not much research has been done in this area, but it has been established devil's claw root possesses a bitter value of 6,000, equal to the main Western bitter, gentian root. It would therefore be expected to possess similar gastro-intestinal properties. Indeed, in the few reported studies on g.i. problems, harpagophytum proved effective in treating such complaints as dyspepsia and conditions relating to the proper functioning of bile salts, the gallbladder, and the enterohepatic circuit. In a related manner, the herb helps to raise cholesterol and fatty acid levels in the blood. As one author points out, devil's claw may be the perfect treatment for elderly people with arthritis, obesity and hyperlipemia.

Drug Interactions & Precautions

Known Interactions
Devil's claw, insofar as its diuretic action increases the renal excretion of sodium and chloride, may potentiate the hyperglycemic and hyperuremic effects of glucose.

Possible Interactions
The anti-inflammatory activity of devil's claw can be seriously inhibited by phenobarbital and certain other sedatives and hypnotics (chloral hydrate, meprobamate, etc., as well as beta-adrenergic blocking agents (propanolol).

Colchicine may increase sensitivity or enhance the response to devil's claw.

This herb's analgesic effects may be additive with other analgesics and anesthetics. It may be inhibited by barbiturates even though CNS depressant effects may occur.

The analgesic property of this herb may be reversed or eliminated by p-chlorophenylalanine, cyproheptadine HCl, and phenobarbital.

The CNS depressant tendency of this analgesic may be potentiated by chlorpoxthixene HCl, haloperidol, and tranquilizers.

The use of diuretics may require dosage adjustments of antidiabetic drugs.

Devil's claw should not be used with methotrimeprazine, a potent CNS depressant analgesic.

Comments
In the absence of other hard data, it may still be assumed observable interactions may occur between the many central nervous system drugs and the psychoactive principles in devil's claw.

Safety Factors & Toxicity

The data supporting the safety of devil's claw is quite extensive, including concomitant toxicity tests with the experimental and clinical work reported in the method of action section, as well as studies designed specifically to test for toxicity.

The LD50 has been established at 34mg/kg and 220 mg/kg, and is therefore possessed of a very weak toxicity. Reports of adverse side effects have been circulated by the British government.

This herb has approval status by the German Commission E as an analgesic.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Preparation & Administration

Use three times daily

Tea or decoction
use 0.10-0.25g of dried tuber

Liquid Extract
use 0.10-0.25ml of 1:1 in 25% alcohol

Tincture
use 0.5-1ml of 1:5 in 25% alcohol

This herb has approval status by the German Commission E.

Recommended daily dosages in Germany are as follows:

1.5 g of the herb for loss of appetite.
4.5 g herb, otherwise.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Note: This Herbal Preparation information is a summary of data from books and articles by various authors. It is not intended to replace the advice or attention of health care professionals.

References

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

British Herbal Pharmacopoeia, British Herbal Medicine Association, 1983.

Caprasse, M. Description, identification et usages therapeutiques de la 'griffe du diable': harpagophytum procumbens DC. Pharm. Belg., 35(2), 143-149, 1980.

Eichler, O. & Koch, C. Uber di antiphlogistiche, analgetische und spasmolytische wirksamkeit von harpagosid. Arzneimittel Forschung, 20(1), 107-109, 1970.

Erdoes, Fontaine, Friehe, Durand, & Poeppinghaus. 1978. Beitrag zur pharmakologie und toxikologie verschiedener extrakte, sowie des harpagosids aus harpagophytum procumbens DC. Planta Medica, 34, 97-108,

Facts and Comparisons. The Lawrence Review of Natural Products. Mar, 1996.

Grahme, R. & B.V. Robinson. Devil's claw (harpagophytum procumbens) - pharmacological and clinical studies. Annals of the Rheumatic Diseases. 40(6), 632, 1981.

Hoppe, H. Einfluss der droge harpagophytum procumbens DC auf diabetes mellitus mit fettstoffwechselstorungen. Erfahrungsheilkunde, 7, 230-233, 1974.

J of Ethopharmacology, Four part series: A drug used in traditional medicine. Harpagophytum procumbens. J of Ethopharmacology 1984, 11(3):245, 259, 13(2):201.

Mowrey, Daniel B., Ph.D. Exper. Psych., Brigham Young University. Director of Nebo Institute of Herbal Sciences. Director of Behavior Change Agent Training Institute. Director of Research, Nova Corp.

Schmidt, S. Phytotherapie beim rheumatischen formankreis. Erfahrungsheilkunde, 5, 152-154, 1973/5).

Schmidt S. Rheumatherapie mit harpagophytum. Therapiewoche. 72, 1072-1074, 1972.

Seeger, P.G. Harpagophytum, ein wirksames phytotherapeutikum. Erfahrungsheilkunde, 8, 1973.

Soulimani, R et al., The role of stomachal digestion on the pharmacological activity of plant extracts, using as an example extracts of Harpagophytum procumbens. Can. J. Physiol. Pharmacol. 1994, 72:1,532.

Tunman, P. & R. Lux. Zur kenntnis der inhaltsoffe aus der wurzel von h.p. Deutscher Apotheker-Zeitung, 1274-1275, 1962; and 395-396, 1963.

Weiss, R.F. Herbal Medicine. Beaconsfield Publishers, LTD, Beaconsfield, England, 1988.

Whitehouse, LW et al., Devil's Clkaw (Harpagophytum procumbens): no evidence for anti-inflammatory activity in the treatment of arthritic disease. Can. Med. Assoc. J. 1983, 129(3):249.

Zimmerman, W. Erfahrungen mit harpagophytum. Physikalische Medizin und. Rehabilitation, 18, 317-319, 1977.

Zorn, B. Uber di antiarthritische wirkung der harpagophytumwurzel. Zeitschrift fur Rheumaforschung, 17, 134-138, 1958.