Devil's Claw
Harpagophytum procumbens
Evidence Rating
Confidence Level
Traditions
Last Updated
Summary
Devil's Claw is one of the best-studied herbal anti-inflammatories in the European phytotherapy tradition, with 14+ clinical trials supporting its use in osteoarthritis and low back pain. At doses providing >=50 mg harpagoside daily, it has demonstrated non-inferiority to diacerhein (for OA) and rofecoxib (for low back pain). It is widely prescribed in Germany and France but remains virtually unknown in US clinical practice, representing one of the most significant gaps between European and American phytotherapy.
Drug Interactions
This herb has significant drug interactions. Do not use if you are taking medications without consulting a healthcare provider first. See detailed interaction information below.
Regulatory Status
| Regulatory Body | Status |
|---|---|
| Commission E (Germany) | âś“ Approved |
| ESCOP (European) | âś“ Approved |
| EMA/HMPC (EU) | âś“ Approved |
Metadata
| Field | Detail |
|---|---|
| Common Names (English) | Devil’s Claw, Grapple Plant, Wood Spider |
| Common Names (German) | Teufelskralle, Afrikanische Teufelskralle |
| Botanical Name | Harpagophytum procumbens DC. and/or Harpagophytum zeyheri Decne. |
| Plant Family | Pedaliaceae |
| Part Used | Secondary storage root tubers (radix) |
| Evidence Quality Rating | Moderate-High — Multiple RCTs, systematic reviews; EMA/HMPC traditional use monograph; Commission E and ESCOP positive monographs |
Approved Indications
German Commission E (Positive Monograph)
- Loss of appetite (bitter tonic)
- Dyspeptic complaints
- Supportive therapy for degenerative disorders of the locomotor system (musculoskeletal pain)
ESCOP (European Scientific Cooperative on Phytotherapy)
- Painful arthrosis (osteoarthritis)
- Tendonitis
- Loss of appetite, dyspepsia
- Recommended use for at least 2-3 months for joint pain associated with osteoarthritis
EMA/HMPC (European Medicines Agency, 2016)
- Traditional use status (not “well-established use”) for:
- Relief of minor joint pain
- Relief of mild digestive disorders (loss of appetite, bloating, flatulence)
- Reference: EMA/CHMP/627057/2015 (published July 12, 2016)
Agreement/Disagreement Among Authorities
- Agreement: All three European authorities recognize musculoskeletal/joint pain as an indication
- Disagreement: The EMA classified Devil’s Claw under “traditional use” rather than “well-established use,” which some researchers have criticized as not reflecting the full weight of clinical evidence. ESCOP gives more specific guidance on osteoarthritis. Commission E also includes digestive indications (bitter tonic properties)
- US status: GRAS for food use; sold as dietary supplement; no FDA-approved therapeutic claims
Conditions Treated
Primary (Evidence-Supported)
- Osteoarthritis (hip, knee, spine) — strongest evidence base
- Chronic non-specific low back pain — multiple RCTs
- General musculoskeletal pain — supportive evidence
Secondary (Traditional/Preliminary Evidence)
- Tendonitis
- Mild rheumatic complaints
- Dyspepsia and loss of appetite (bitter tonic)
Mechanism of Action
Key Active Compounds
- Harpagoside (iridoid glycoside) — primary marker compound; 0.5-3% in dried tubers
- Harpagide (iridoid glycoside)
- Procumbide (iridoid glycoside)
- 8-p-coumaroylharpagide
Pharmacological Mechanisms
- Inhibition of pro-inflammatory pathways: Harpagoside and whole extracts inhibit the synthesis of pro-inflammatory eicosanoids (via COX-2 and iNOS suppression)
- Cytokine modulation: Reduces TNF-alpha, IL-1beta, and IL-6 production in macrophages [Source: Fiebich et al., 2001]
- NF-kB pathway inhibition: Devil’s claw extracts suppress NF-kB activation, a master regulator of inflammatory gene expression
- Matrix metalloproteinase inhibition: May protect cartilage by inhibiting MMPs involved in cartilage degradation
- Analgesic effects: Mechanism not fully elucidated; may involve both peripheral anti-inflammatory and central analgesic pathways
Important Note on Whole Extract vs. Isolated Harpagoside
The clinical evidence is primarily for whole aqueous or ethanolic extracts, not isolated harpagoside. Some researchers argue that the multi-compound extract provides synergistic effects beyond what harpagoside alone delivers. Harpagoside serves as a marker for standardization, but it is not the sole active compound. [CONTESTED — some researchers attribute primary activity to harpagoside; others emphasize the whole phytocomplex]
Clinical Evidence Summary
Systematic Reviews and Meta-Analyses
- Brien et al. (2006): Systematic review of 12 trials; concluded moderate evidence for use in osteoarthritis and low back pain at doses >=50 mg harpagoside/day [Source: J Rheumatol 2006]
- Gagnier et al. (2004): Cochrane-affiliated review; found strong evidence for aqueous extract at 50 mg harpagoside/day for acute LBP exacerbations; moderate evidence for 60 mg harpagoside/day for OA [Source: BMC Complement Altern Med 2004]
Key Individual Trials
Low Back Pain
| Study | Design | N | Intervention | Comparator | Duration | Key Result |
|---|---|---|---|---|---|---|
| Chrubasik et al. (1996) | RCT, double-blind | 197 | Aqueous extract (50 mg or 100 mg harpagoside/day) | Placebo | 4 weeks | Dose-dependent pain reduction; 50 mg group significantly better than placebo |
| Chrubasik et al. (1999) | RCT, double-blind | 183 | Aqueous extract (60 mg harpagoside/day) | Placebo | 4 weeks | 9/52 pain-free (harpagoside) vs. 1/54 (placebo); significant |
| Chrubasik et al. (2001) | Open, randomized | 88 | Doloteffin (60 mg harpagoside/day) | Rofecoxib 12.5 mg/day | 6 weeks | Non-inferior; ~20% improvement in Arhus index for both groups |
Osteoarthritis
| Study | Design | N | Intervention | Comparator | Duration | Key Result |
|---|---|---|---|---|---|---|
| Chantre et al. (2000) | RCT, double-blind | 122 | Harpadol (57 mg harpagoside/day) | Diacerhein 100 mg/day | 4 months | Non-inferior; equivalent reduction in pain intensity (VAS) |
| Leblan et al. (2000) | RCT, double-blind | 104 | Aqueous extract (60 mg harpagoside/day) | Placebo | 4 months | Significant improvement in VAS pain and Lequesne index |
| Warnock et al. (2007) | RCT, double-blind | 259 | 2610 mg/day extract (proprietary) | Placebo | 8 weeks | Significant improvements in pain, stiffness, function (WOMAC) |
Effect Sizes
- Low back pain: ~30-35% reduction in Total Pain Index vs. ~5-10% for placebo over 4 weeks
- Osteoarthritis: Pain reduction on VAS comparable to diacerhein and mild NSAIDs; onset of effect typically 2-4 weeks; optimal results at 8-16 weeks
European vs. US/Anglophone Consensus
| Aspect | European Position | US/Anglophone Position |
|---|---|---|
| Clinical use | Widely prescribed in Germany, France; available as registered herbal medicine | Niche supplement; rarely recommended by physicians |
| Evidence recognition | Three-level monograph support (Commission E, ESCOP, EMA) | Natural Medicines Database rates as “Possibly Effective” for OA and back pain |
| Prescribing | Commonly recommended by German physicians and Heilpraktiker for OA and LBP as first-line or adjunctive therapy | Virtually absent from US clinical guidelines |
| Insurance | May be partially covered by German statutory health insurance | Not covered by US insurance |
| Research tradition | Decades of German/South African research; Chrubasik group prolific | Limited US-based research; occasional UK/Australian reviews |
Key gap: Devil’s Claw represents perhaps the single largest discrepancy between European and US phytotherapy for musculoskeletal conditions. The evidence base would likely warrant inclusion in US integrative medicine guidelines if it were more widely known.
Safety Profile
Contraindications
- Peptic ulcer disease / gastric hyperacidity: Devil’s Claw stimulates gastric acid secretion
- Gallstones: May increase bile production
- Pregnancy: Possibly unsafe; may harm fetus; traditional use as abortifacient in some cultures
- Cardiac arrhythmias: Potential effects on heart rate and rhythm (theoretical; based on in vitro data)
Drug Interactions
- Warfarin/anticoagulants: May potentiate anticoagulant effects; case report of purpura in patient on warfarin + Devil’s Claw. Monitor INR
- Antiarrhythmics: Theoretical interaction; avoid concurrent use
- NSAIDs: Potential additive anti-inflammatory effects (may be used advantageously in some cases)
- CYP450 substrates: May inhibit CYP2C9, CYP2C19, CYP3A4 — potential for pharmacokinetic interactions
- Antihypertensives: May affect blood pressure
- Antacids/PPIs: Opposing effects on gastric acid
Side Effects
- Generally well-tolerated in clinical trials
- Most common: mild GI complaints (diarrhea, nausea, abdominal pain) in ~3-8% of patients
- Headache (rare)
- Allergic reactions (rare)
- Fewer side effects than diacerhein in the Chantre (2000) comparison trial
Pregnancy and Lactation
- Pregnancy: Contraindicated. Possible oxytocic effects; traditional use as abortifacient; insufficient safety data
- Lactation: Insufficient data; avoid use
Clinical Dosage
Recommended Forms and Doses
| Form | Daily Dose | Harpagoside Content | Notes |
|---|---|---|---|
| Aqueous extract (Doloteffin) | 2,400 mg/day (2 x 480 mg tablets, 2-3x/day) | 50-60 mg harpagoside/day | Best-studied form; Ardeypharm product |
| Powdered root (Harpadol) | 2,600 mg/day (6 capsules/day) | 57 mg harpagoside/day | Arkopharm product; used in Chantre 2000 trial |
| Dried root tuber (cut/powdered) | 1.5-4.5 g/day as decoction | Variable | Traditional preparation; less standardized |
| Ethanolic extract | Variable by product | Should provide >=50 mg harpagoside/day | Less studied than aqueous extracts |
| Tincture (1:5) | Variable | Lower harpagoside delivery | Not the preferred clinical form |
Key Dosing Principles
- Minimum effective dose: >=50 mg harpagoside/day for analgesic/anti-inflammatory effects
- Optimal dose: 60 mg harpagoside/day (best evidence base)
- Onset of action: 2-4 weeks; inform patients that benefit builds over time
- Duration: ESCOP recommends minimum 2-3 months for osteoarthritis
- Aqueous extraction preferred: Aqueous extracts have higher harpagoside content per gram than ethanolic extracts
Key European Products
- Doloteffin (Ardeypharm, Germany) — aqueous extract; most-studied product
- Harpadol (Arkopharm, France) — powdered root in capsules
- Rivoltan (Germany) — dry extract tablets
- Harpagophytum Arkocaps (various European markets)
Sources
- Brien S et al. Devil’s Claw (Harpagophytum procumbens) as a treatment for osteoarthritis: a review of efficacy and safety. J Rheumatol. 2006;14(3):17-21.
- Gagnier JJ et al. Harpagophytum procumbens for osteoarthritis and low back pain: a systematic review. BMC Complement Altern Med. 2004;4:13.
- Chrubasik S et al. Treatment of low back pain exacerbations with willow bark extract: a randomized double-blind study. Am J Med. 2000;109(1):9-14.
- Chantre P et al. Efficacy and tolerance of Harpagophytum procumbens versus diacerhein in treatment of osteoarthritis. Phytomedicine. 2000;7(3):177-183.
- EMA/HMPC. European Union herbal monograph on Harpagophytum procumbens. EMA/CHMP/627057/2015 (2016).
- Alternative Medicine Review. Harpagophytum procumbens (Devil’s Claw) Monograph. Vol 13, No 3, 2008.
- Warnock M et al. Effectiveness and safety of Devil’s Claw tablets in patients with general rheumatic disorders. Phytother Res. 2007;21:1228-1233.
Connections
- Compare with Willow Bark — both underappreciated in US practice for similar indications
- Compare with Boswellia — alternative oral anti-inflammatory for OA
Related Herbs
Frankincense / Boswellia
Boswellia serrata
Boswellia serrata (Indian frankincense) is an increasingly important anti-inflammatory herb with a growing evidence base in osteoarthritis, particularly knee OA. Its unique mechanism -- dual inhibition of 5-LOX and NF-kB, distinct from the COX pathway targeted by NSAIDs -- makes it a complementary rather than duplicative therapeutic option. Multiple RCTs with proprietary extracts (5-Loxin, Aflapin) show significant improvements in pain and function, with onset as early as 7 days. However, unlike most other herbs in this module, Boswellia lacks a full EMA herbal monograph, and its European regulatory position is less developed than its Ayurvedic tradition and modern clinical evidence would warrant.
Meadowsweet
*Filipendula ulmaria*
Meadowsweet (Filipendula ulmaria) is historically significant as the plant from which aspirin derived its name -- "a-spirin" from "Spiraea," the old genus name for meadowsweet. The flowers and aerial parts contain salicylaldehyde, methyl salicylate, and salicin, along with flavonoids (notably spiraeoside) and tannins (rugosins). It holds EMA traditional use status for supportive treatment of common cold and as adjuvant for mild joint pain, but lacks Commission E or ESCOP monographs. No clinical trials exist for meadowsweet monotherapy. Paradoxically, despite its salicylate content, meadowsweet has been traditionally used to soothe the stomach -- in contrast to aspirin's well-known gastric irritation. This gastroprotective effect is attributed to its tannin and mucilage content, which may buffer the salicylate effects. Drug interactions with NSAIDs and anticoagulants are possible due to salicylate content.
Willow Bark
Salix spp.
Willow Bark holds EMA "well-established use" status for low back pain -- the highest evidence tier available for herbal medicines in Europe. At 240 mg salicin/day, it demonstrated non-inferiority to rofecoxib (Vioxx) 12.5 mg/day in a head-to-head RCT for low back pain, at roughly 40% lower cost. Critically, willow bark is NOT simply "natural aspirin": it does not acetylate COX enzymes, has a broader mechanism of action, and produces far less GI toxicity. Despite this evidence, it remains rarely used in US clinical practice.