Botanical name

African Devil's Claw - Harpagophytum procumbens (Burch.) DC.

Family

Sesame family (Pedaliaceae)

Information about the plant

The Devil's claw grows in the sandy areas of the savannas of southern Africa (Namibia, South Africa, Botswana). The genus name, Harpagophytum, derived from Greek "harpagus" (= grappling hook) and the English name "Devil's claw," refer to the fruits of the plant. There are egg-shaped seed capsules with several arm-like growths that after bursting the capsules apart spread out claw-like and very woody. With their sharp barbs, they dig into the hooves of animals and cause infections that can lead to death. The up to 6cm long reddish-purple, gloxinia style flowers in the axils are very decorative. The herbaceous plant is on the ground, with long shoots. The leaves are stalked and deeply lobed, and they are usually opposite, at the growing ends they are often constantly alternate.

Medicinally used parts of plants (herbal drug)

The bulbous, lateral roots of the outgoing (secondary) storage roots are used. They are dug up, washed and freshly sliced in 0.5 to 1.5cm thick slices and then dried. They are very hard, so they must be crushed when fresh. The roots can also be obtained from another Harpagophytum species, namely H. zeyheri Decne. The drug is imported from south-western Africa and is collected in the wild, but also increasingly from farms.

Constituents of the herbal drug

Devil's claw contains iridoid glycosides, phenolic glycosides and saccharides.

Quality of the drug

The quality of the following drugs or drug preparations is specified in the European Pharmacopoeia (Ph. Eur.):

• Devil's claw root (Harpagophyti radix)
• Devil's claw root dried extract (Harpagophyti extractum siccum)

Medical applications

Recognised medical use

Loss of appetite, dyspeptic complaints (Commission E, ESCOP), supportive therapy of degenerative disorders of the musculoskeletal system (Commission E ) to treat pain associated with osteoarthritis and back pain (ESCOP). The HMPC has classified Devil's claw root as a traditional herbal medicinal product (see "traditional use").

Traditional use

Devil's claw root was categorised by the HMPC as a traditional herbal medicine (§ 39a AMG). Based on many years of experience, Devil's claw root can be used to improve slight joint pain and digestive disturbances (e.g. wind) and loss of appetite.

Herbal drug preparations in finished dosage forms

• chopped or coarsely powdered drug to prepare tea
• dried extracts in tablets and capsules
• alcoholic extracts (including tincture) in drops
• mother tincture in drops

Dosage

Prepared drugs: see package insert;
Tea infusion: drink a cup Devil´s claw root three times a day. For joint pain is the daily dose is 4.5g of the drug, and 1.5g for indigestion, each to be taken in three individual doses. To stimulate the appetite drink the infusion half an hour before meals, and after meals for indigestion.

Preparation of a tea

Pour 300ml of boiling water over 4.5g or 1.5g of finely chopped Devil's claw root and let it stand for 8 hours at room temperature, then strain and drink in three portions.

Notes

Do not take devil's claw with gastric and duodenal ulcers, and for gall bladder complaints only after consultation with the doctor. Do not use during pregnancy and when breast-feeding without consulting a doctor since there are as yet no findings on its safety.

Side effects

Rarely observed: nausea, vomiting, diarrhea, dizziness and headaches; very rare: hypersensitivity reactions such as rash, hives and even anaphylactic shock.

Interactions

None known.

References

Herbal drug monographs

HMPC, Commission E, ESCOP, WHO (Vol. 3)

Further literature

Wichtl: Teedrogen und Phytopharmaka, pg. 324
Schilcher: Leitfaden Phytotherapie, pg. 263
Van Wyk: Handbuch der Arzneipflanzen, pg. 165
Kommentar zum Europäischen Arzneibuch (Devil's claw root, no. 1095; Devil's claw root dried extract, no. 1871)