A martial name for a remarkable plant: devil’s claw sounds like anything but a medicinal remedy. Yet Harpagophytum procumbens is one of the best-documented botanical active substances in modern phytotherapy – with more than 65 clinical studies, a largely clarified mechanism of action and a safety profile that is superior to that of some synthetic anti-inflammatory drugs. Anyone suffering from joint or back pain and looking for plant-based alternatives can hardly avoid it.
A plant of the Kalahari – origin and botany
Devil’s claw is native to the savannas of South Africa, Namibia, Botswana and Zimbabwe. It grows on sandy, nutrient-poor soils under arid to semi-arid conditions – a plant that survives extreme drought by storing large amounts of water and nutrients in underground storage roots. These storage roots, which can reach up to one metre deep into the ground, are the medicinally used part of the plant.
Devil’s claw owes its name to its characteristic fruits: woody capsules with strong, outward-curving hooks that attach themselves to animal fur – and even to the leather of shoe soles – helping the plant to spread. The plant itself is inconspicuous; the dried and ground root tubers used in phytotherapy appear externally rather unremarkable.
In South Africa and Namibia, devil’s claw has a long tradition in folk medicine – especially for pain, fever and digestive complaints. It reached Europe in the 1950s, where it was first systematically studied phytochemically in Germany and is now one of the best-selling herbal remedies for rheumatic complaints.
The active substance harpagoside – and how it works
The pharmacologically most relevant constituents of devil’s claw are iridoid glycosides, above all harpagoside – alongside harpagide and procumbide. These are complemented by flavonoids such as fisetin, kaempferol and luteolin, as well as phenylpropanoids and triterpenes, which have antioxidant properties.
Harpagoside is regarded as the marker compound: it selectively inhibits cyclooxygenase-2 (COX-2) – the same enzyme that is also blocked by common non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or diclofenac. In addition, devil’s claw inhibits lipoxygenase and leukotriene biosynthesis, meaning it acts at several points in the inflammatory process.
The quality of the finished product depends largely on whether the harpagoside content is analytically tested and transparently declared. The quality of the root, the age at harvest and the extraction method determine the harpagoside content – which is why standardised extracts with a declared active substance content are preferable to simple root powder.
| Constituent class | Main representatives | Documented properties |
|---|---|---|
| Iridoid glycosides | Harpagoside, harpagide | COX-2 inhibition, analgesic |
| Flavonoids | Fisetin, kaempferol, luteolin | Antioxidant, inflammation-modulating |
| Phenylpropanoids | Acteoside, isoacteoside | Antioxidant |
| Triterpenes | — | Inflammation-modulating |
Joints and osteoarthritis – what clinical studies show
Devil’s claw is one of the few medicinal plants that has been tested in direct comparative studies against approved medicines – and has held its own.
A randomised, active-controlled clinical study (Farpour et al., 2021, Evidence-Based Complementary and Alternative Medicine) investigated 60 patients with knee osteoarthritis (Kellgren-Lawrence grade 1–2). Daily Harpagophytum tablets (2 × 480 mg) over four weeks were compared with the NSAID meloxicam (15 mg/day) over ten days. Assessment was carried out using established pain scales (VAS, WOMAC, Oxford Knee Score) after 2, 4 and 8 weeks. Result: both groups showed significant improvements in pain and function – without statistically significant differences between the groups. Devil’s claw was therefore comparable to meloxicam, while showing a significantly better tolerability profile.
An older but methodologically strong prospective multicentre study (Leblan et al., 2000, Joint Bone Spine) compared Harpagophytum over four months with diacerein – an osteoarthritis medicine approved in Europe – in knee and hip osteoarthritis. Again: comparable efficacy, with fewer adverse effects under the herbal treatment.
The Cochrane review by Cameron & Chrubasik (2014) summarised the available evidence on oral herbal therapies for osteoarthritis (Cameron & Chrubasik, Cochrane Database, 2014) and found moderate evidence for pain reduction in hip and knee osteoarthritis with Harpagophytum – with one limitation: study quality varies considerably, and direct comparisons with modern guideline medicines for osteoarthritis are still lacking in large RCTs.
Back pain – the strongest clinical evidence
For non-specific chronic back pain, the data for devil’s claw is even more robust than for osteoarthritis.
A systematic review (Gagnier, Chrubasik & Manheimer, 2004, BMC Complementary and Alternative Medicine) identified strong evidence for the efficacy of an aqueous Harpagophytum extract in acute exacerbations of chronic back pain. A relevant finding was that patients in the treatment group required significantly fewer additional analgesics than those in the placebo group.
The Cochrane review on herbal medicines for low back pain (Oltean et al., 2014, Cochrane Database Syst Rev) confirms: devil’s claw extract is the best-studied herbal remedy in this indication area – with evidence supporting its use as an adjunctive option, although the overall study quality means further research remains desirable.
Devil’s claw as part of a natural joint formula
Mobil Essentia by Natura Nova combines devil’s claw extract with other well-established plant substances – supplemented with carefully selected micronutrients. Made in Switzerland according to GMP standards, laboratory tested.
Safety and tolerability – better than its reputation
One of the most important characteristics of devil’s claw is its pronounced safety profile. In a comprehensive bibliographic review (Brendler, 2021, Pharmaceuticals) – the most complete documentation of the scientific literature on Harpagophytum to date – it is described as one of the best-documented safety profiles among phytotherapeutics.
In controlled studies, mild adverse effects occurred in around 3 percent of users, mainly in the gastrointestinal tract – and not more frequently than in the respective placebo control groups. By comparison, gastrointestinal side effects are significantly more common with classical NSAIDs, at 15–30 percent, especially with long-term use.
Important restrictions: Devil’s claw should not be used in cases of gastric ulcers or active gastritis – its bitter substances stimulate gastric acid production. Interactions with anticoagulants (blood thinners) are possible and should be clarified with a doctor. Devil’s claw is contraindicated during pregnancy.
From bush medicine to modern phytopharmacy – what this means for quality
Devil’s claw is now one of the most important export products of herbal medicine from southern Africa – and this is precisely where one of the greatest challenges for consumers lies: the quality of commercially available products varies considerably.
The storage roots are usually harvested after the plant has grown for several years. Excessive harvesting in certain regions of Namibia and South Africa has in the past led to population declines – making sustainable harvesting guidelines and certified supply chains relevant quality features.
Three factors are decisive for efficacy: the harpagoside content of the extract, the extraction method – aqueous extracts often show better bioavailability in studies than ethanolic extracts – and the standardisation of the finished product, meaning whether the harpagoside content is analytically tested and declared. Products that merely declare “devil’s claw root powder” without specifying the active substance content do not allow such verification.
Practical classification: who is devil’s claw suitable for?
Devil’s claw is not a miracle cure and not a substitute for medical diagnosis in serious joint diseases. What it can provide is a well-tolerated, plant-based support option for mild to moderate complaints of the musculoskeletal system – especially degenerative joint diseases and chronic back pain.
The data supports use as a course of treatment over several weeks; the effect usually does not occur immediately, but builds up over two to four weeks. This distinguishes devil’s claw from synthetic analgesics – but also requires users to have realistic expectations.
For people who tolerate NSAIDs poorly or rely on them long term, devil’s claw in standardised and documented quality represents a scientifically grounded alternative – a statement that can be made for very few herbal active substances with a comparable evidence base.
This article is for informational purposes only. Food supplements are not a substitute for a balanced diet and a healthy lifestyle. If you have health-related questions, especially in the case of chronic illness or medication use, please consult a medical professional.
Sources
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Farpour HR, Rajabi N, Ebrahimi B. (2021). The Efficacy of Harpagophytum procumbens (Teltonal) in Patients with Knee Osteoarthritis: A Randomized Active-Controlled Clinical Trial. Evidence-Based Complementary and Alternative Medicine, 2021, 5596892. https://doi.org/10.1155/2021/5596892
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Brendler T. (2021). From Bush Medicine to Modern Phytopharmaceutical: A Bibliographic Review of Devil's Claw (Harpagophytum spp.). Pharmaceuticals, 14(8), 726. https://doi.org/10.3390/ph14080726
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Gagnier JJ, Chrubasik S, Manheimer E. (2004). Harpagophytum procumbens for osteoarthritis and low back pain: A systematic review. BMC Complementary and Alternative Medicine, 4, 13. https://doi.org/10.1186/1472-6882-4-13
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Cameron M, Chrubasik S. (2014). Oral herbal therapies for treating osteoarthritis. Cochrane Database of Systematic Reviews, 2014(5), CD002947. https://doi.org/10.1002/14651858.CD002947.pub2
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Oltean H, Robbins C, van Tulder MW et al. (2014). Herbal medicine for low-back pain. Cochrane Database of Systematic Reviews, 2014(12), CD004504. https://doi.org/10.1002/14651858.CD004504.pub4
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Leblan D, Chantre P, Fournié B. (2000). Harpagophytum procumbens in the treatment of knee and hip osteoarthritis. Joint Bone Spine, 67(5), 462–467. PubMed
