Home Ingredients Flexigo™ (Devil's Claw Joint Health)
Joint Health

Flexigo™ (Devil's Claw Joint Health)

Harpagophytum procumbens
Evidence Level
Limited
2 Clinical Trials
5 Documented Benefits
2/5 Evidence Score

Flexigo™ is a standardized Devil'S claw extract (Harpagophytum procumbens, also Harpagophytum zeyheri) from Southern Africa — developed by Nexira (France) as natural joint health solution. Distinguished by standardized harpagoside content up to 20% (HPLC method), 100% Devil's Claw (carrier-free), sustainable wild-harvest sourcing from Southern African partnerships, and EFSA pending claims for joint health. Used for joint comfort, mobility, and flexibility, particularly in active people and aging populations.

Studied Dose 1.8-3 g/day extract providing 50-100 mg harpagosides daily; varies by standardization
Active Compound Harpagosides (iridoid glycosides) are the marker actives; Flexigo is a high-standardization Devil's Claw extract, with harpagoside content up to about 20 percent by HPLC (Nexira).

Benefits

Joint Pain and Mobility (Clinical Evidence)

Human studies of Devil's Claw extracts report pain reduction and better mobility in people with osteoarthritis and low back pain. The osteoarthritis studies were open-label and uncontrolled; the strongest evidence is two placebo-controlled trials of extracts standardized to 50 to 100 mg harpagoside per day for low back pain. The Flexigo brand itself has not been tested in a published trial, so this evidence is for Devil's Claw extract generally, not this specific product.

Supported by Trial 1

Anti-Inflammatory Activity (Laboratory Evidence)

In laboratory cell and animal models, harpagoside and other iridoid compounds inhibit COX-2, lipoxygenase and the NF-kB pathway. This is a plausible anti-inflammatory mechanism, but reduction of blood inflammation markers has not been demonstrated in human trials, which measured pain and function rather than markers.

Supported by Trial 1, Trial 2

EFSA Pending Claims

Two pending EFSA claims for Harpagophytum procumbens: (1) 'Helps to maintain joint health'; (2) 'Helps to maintain flexible joints and good mobility'. These claims sit unassessed in the EFSA botanical backlog and have not been authorised; pending status is not an endorsement of efficacy.

Athletic Use (Not Studied)

Devil's Claw has not been tested in athletes or for exercise recovery. The human studies were done in older adults with osteoarthritis, rheumatic joint pain or low back pain, so any use for sport-related joint stress is an extrapolation, not a studied outcome.

Supported by Trial 1, Trial 2

Carrier-Free 100% Active Ingredient

Flexigo™ is 100% Devil's Claw (no carrier); allows precise dosing and high active concentration. Distinguishes from products diluted with maltodextrin or other fillers.

Supported by Trial 1, Trial 2

Mechanism of action

1

Harpagoside Anti-Inflammatory Activity

Harpagoside (and harpagide, procumbide) are iridoid glycosides — primary actives. Inhibit COX-2, lipoxygenase pathway, NF-κB activation. Mechanism similar in direction to NSAIDs but weaker effect; better tolerability.

2

Cytokine Modulation

Reduces pro-inflammatory cytokine production (TNF-α, IL-1β, IL-6); contributes to joint inflammation reduction.

3

Cartilage Protection (Theoretical)

Some animal evidence for chondroprotective effects — protection of cartilage from inflammatory degradation. Clinical translation incomplete.

4

Sustainable Wild-Harvest Sourcing

Devil's Claw grows wild in Southern Africa (Namibia, Botswana, South Africa); roots harvested sustainably with rotation systems. Nexira maintains long-term sustainable supply chain partnerships.

Clinical trials

1
Devil's Claw for Osteoarthritis (Evidence Synthesis, Not a Single Trial)
PubMed

Evidence review of Devil's Claw clinical trials for arthritis pain.

Pooled across multiple osteoarthritis trials.

Open-label, uncontrolled studies report pain reduction and better mobility in osteoarthritis of the hip and knee. The placebo-controlled evidence for Devil's Claw is mainly in low back pain, not osteoarthritis, so 'versus placebo' does not apply to the osteoarthritis data. No study tested the Flexigo brand. This card summarises several studies and is not a single randomized trial.

2
Devil's Claw Compared With an NSAID (One Small Pilot Trial)
PubMed

One randomized double-blind pilot comparing an aqueous Devil's Claw extract with rofecoxib for low back pain.

Adults with acutely exacerbated low back pain.

In one 88-patient pilot, an aqueous Devil's Claw extract (Doloteffin, 60 mg harpagoside per day) showed no significant difference from rofecoxib 12.5 mg over 6 weeks, but the authors stated the study was too small to prove equivalence. This was an underpowered pilot in low back pain, not a definitive comparison, and being comparable to a drug in one small study does not make Devil's Claw a substitute for prescribed medication.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated.
GI distress (nausea, diarrhea) — most common.
Headache.
Theoretical bleeding risk at high doses (modest antiplatelet effects).
Allergic reactions rare.
Bitter taste of extract.

Important Drug interactions

Anticoagulants — theoretical bleeding risk; modest at typical doses; consult.
Diabetes medications — modest hypoglycemic effects; monitor.
Gastric ulcers / severe GERD — Devil's Claw may stimulate gastric acid; avoid with active ulcer disease.
Anti-arrhythmic medications — theoretical effects on cardiac function.
Pregnancy — uterotonic effects historically; avoid supplementation in pregnancy.
Lactation — limited safety data; avoid.

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Frequently asked questions about Flexigo™ (Devil's Claw Joint Health)

What is Flexigo?

Flexigo™ is a standardized Devil'S claw extract (Harpagophytum procumbens, also Harpagophytum zeyheri) from Southern Africa — developed by Nexira (France) as natural joint health solution.

What is Flexigo used for?

Flexigo is researched primarily for Joint Health. Human studies of Devil's Claw extracts report pain reduction and better mobility in people with osteoarthritis and low back pain.

What is the recommended dosage of Flexigo?

The clinically studied dose is 1.8-3 g/day extract providing 50-100 mg harpagosides daily; varies by standardization Always follow the product label and check with a healthcare provider for personal advice.

Is Flexigo safe, and does it have side effects?

For most healthy adults, Flexigo is well tolerated at studied doses. Reported effects can include: Generally well-tolerated. GI distress (nausea, diarrhea) — most common. It may also interact with some medications. Flexigo is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Flexigo interact with any medications?

Possible interactions include: Anticoagulants — theoretical bleeding risk; modest at typical doses; consult. Diabetes medications — modest hypoglycemic effects; monitor. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Flexigo?

NutraSmarts rates the evidence for Flexigo as Limited (2 out of 5). It is backed by 2 clinical trials and 6 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(6 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Wegener T, Lüpke NP. Treatment of patients with arthrosis of hip or knee with an aqueous extract of devil's claw (Harpagophytum procumbens DC.). Phytother Res. 2003;17(10):1165-1172. doi: 10.1002/ptr.1322.PubMedUsed to support: Uncontrolled, open-label drug-surveillance study in 75 patients with hip or knee osteoarthritis taking an aqueous Devil's Claw extract (Doloteffin, 2400 mg providing 50 mg harpagoside daily) for 12 weeks. WOMAC and pain scores fell by roughly 22 to 26 percent, but with no placebo group these changes cannot be separated from natural symptom fluctuation and expectation. The product tested was not Flexigo.
  2. Warnock M, McBean D, Suter A, Tan J, Whittaker P. Effectiveness and safety of Devil's Claw tablets in patients with general rheumatic disorders. Phytother Res. 2007;21(12):1228-1233. doi: 10.1002/ptr.2288.PubMedUsed to support: Single-group open study with no placebo control in 259 UK patients with degenerative rheumatic disorders taking a Devil's Claw product (Bioforce, A.Vogel) for 8 weeks. Pain, stiffness and function improved from baseline and 60 percent of patients reduced or stopped other pain medication. Without a control group the true effect size is uncertain, and the product was not Flexigo.
  3. Gagnier JJ, van Tulder M, Berman B, Bombardier C. Herbal medicine for low back pain. Cochrane Database Syst Rev. 2006;2006(2):CD004504. doi: 10.1002/14651858.CD004504.pub3.PubMedUsed to support: Cochrane review of herbal medicines for low back pain (2006 version). Two high-quality randomized trials gave strong evidence that Devil's Claw standardized to 50 or 100 mg harpagoside per day beat placebo for short-term low back pain, and one trial found it roughly equivalent to low-dose rofecoxib. This review covered low back pain, not osteoarthritis or athletic use, and a 2014 update of it now exists.
  4. Huang TH, Tran VH, Duke RK, Tan S, Chrubasik S, Roufogalis BD, Duke CC. Harpagoside suppresses lipopolysaccharide-induced iNOS and COX-2 expression through inhibition of NF-kappa B activation. J Ethnopharmacol. 2006;104(1-2):149-155. doi: 10.1016/j.jep.2005.08.055.PubMedUsed to support: Laboratory cell-based study showing harpagoside suppresses LPS-induced iNOS and COX-2 expression by inhibiting NF-kB activation. This describes a plausible anti-inflammatory mechanism in vitro and is not evidence of reduced inflammation in people.
  5. Grant L, McBean DE, Fyfe L, Warnock AM. A review of the biological and potential therapeutic actions of Harpagophytum procumbens. Phytother Res. 2007;21(3):199-209. doi: 10.1002/ptr.2029.PubMedUsed to support: Narrative review of the pharmacology and reported clinical effects of Devil's Claw in joint and musculoskeletal complaints. As a review it summarises other studies rather than providing direct trial evidence, and it concerns Devil's Claw generally, not the Flexigo brand.
  6. Chrubasik S, Model A, Black A, Pollak S. A randomized double-blind pilot study comparing Doloteffin and Vioxx in the treatment of low back pain. Rheumatology (Oxford). 2003;42(1):141-148. doi: 10.1093/rheumatology/keg053.PubMedUsed to support: Randomized double-blind pilot in 88 adults with acutely exacerbated low back pain comparing an aqueous Devil's Claw extract (Doloteffin, 60 mg harpagoside per day) with rofecoxib 12.5 mg per day over 6 weeks. Pain fell similarly in both groups (about 23 percent versus 26 percent) with no significant difference, but the authors concluded the trial was too small to demonstrate equivalence. It tested a low back pain population, not osteoarthritis, and not the Flexigo brand.