# Devil’s claw (Harpagophytum procumbens)

**Harpagophytum procumbens* DC., with *Harpagophytum zeyheri*; in pharmacy *Harpagophyti radix*, the root*

**Known today as.** *Harpagophytum procumbens*, a plant of the family Pedaliaceae, whose root is the medicine. The European assessment report notes that the secondary tubers contain about twice as much of the bitter harpagoside as the primary ones, and that the drug is sometimes adulterated with harpagoside-poor primary roots or with other bitter plants.

Kind: Plant

> **Caution.** Not for people with an active stomach or duodenal ulcer, and those with gallstones should ask a doctor first. Not for anyone under eighteen, for want of data. Joint pain with swelling, redness, or fever should be examined by a doctor. Digestive upsets, headache, vertigo, and allergic reactions such as rash, hives, or facial swelling have been reported.

## What was it used for?

A modern remedy for joint pain and the digestion, with no history in the European herbals read for this entry. It is used for minor joint pain and, as a bitter, for bloating, flatulence, and loss of appetite.

## What does modern science say?

The European Medicines Agency’s herbal committee accepts the root as a traditional herbal medicine, “exclusively based upon long-standing use,” for the relief of minor joint pain, and for mild digestive disorders such as bloating and flatulence where there is temporary loss of appetite (monograph of 2016). Its assessment report finds iridoid glucosides, chiefly harpagoside, “extremely bitter,” at 0.8 to 3 per cent in this species, with the phenolic glycoside acteoside and much sugar, mainly stachyose. A 2008 review of the safety of devil’s claw in 28 clinical trials for arthritic and low back pain found minor adverse events, mainly digestive, in about 3 per cent of patients, and in none of the double-blind studies more than on placebo, but called long-term safety data “urgently needed.”

## Pharmacognosy and toxicology

- **harpagoside**: chief of the iridoid glucosides, 0.8 to 3 per cent, “extremely bitter”; about twice as much in the secondary tubers
- **acteoside**: a phenolic glycoside
- **stachyose**: most of the sugar

**Mechanism.** Not established in the sources read for this entry.

**Standing.** European Union herbal monograph (2016): traditional use, “exclusively based upon long-standing use,” for minor joint pain and for mild digestive disorders with loss of appetite.

## Sources

- European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Harpagophyti radix (Devil’s Claw Root)*. EMA/HMPC/627057/2015, 12 July 2016.
- European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Harpagophyti radix*. EMA/HMPC/627058/2015, 12 July 2016.
- Vlachojannis J, et al. (2008). Systematic review on the safety of Harpagophytum preparations for osteoarthritic and low back pain. *Phytotherapy research : PTR*. PMID 18236448.
- European Medicines Agency, Committee on Herbal Medicinal Products. *European Union herbal monograph on Harpagophyti radix (Devil’s Claw Root)*. EMA/HMPC/627057/2015, 12 July 2016.
- European Medicines Agency, Committee on Herbal Medicinal Products. *Assessment report on Harpagophyti radix*. EMA/HMPC/627058/2015, 12 July 2016.
- Vlachojannis J, et al. (2008). Systematic review on the safety of Harpagophytum preparations for osteoarthritic and low back pain. *Phytotherapy research : PTR*. PMID 18236448.

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*Devil’s claw.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-16. The Thinking Press. https://thethinkingpress.org/materia-medica/devil-s-claw

Historical description, not medical advice.