Devil's Claw (Harpagophytum procumbens) as a tool for helping with Pain (general)

An evidence-based systematic review including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interaction, adverse effects, toxicology, and dosing.

Background The objective of this review is to determine the effectiveness of Harpagophytum procumbens preparations in the treatment of various forms of musculoskeletal pain. Methods Several databases and other sources were searched to identify randomized controlled trials, quasi-randomized controlled trials, and controlled clinical trials testing Harpagophytum preparations in adults suffering from pain due to osteoarthritis or low back pain. Results Given the clinical heterogeneity and insufficient data for statistical pooling, trials were described in a narrative way, taking into consideration methodological quality scores. Twelve trials were included with six investigating osteoarthritis (two were identical trials), four low back pain, and three mixed-pain conditions. Conclusions There is limited evidence for an ethanolic Harpagophytum extract containing less than <30 mg harpagoside per day in the treatment of knee and hip osteoarthritis. There is moderate evidence of effectiveness for (1) the use of a Harpagophytum powder at 60 mg harpagoside in the treatment of osteoarthritis of the spine, hip and knee; (2) the use of an aqueous Harpagophytum extract at a daily dose of 100 mg harpagoside in the treatment of acute exacerbations of chronic non-specific low back pain; and (3) the use of an aqueous extract of Harpagophytum procumbens at 60 mg harpagoside being non-inferior to 12.5 mg rofecoxib per day for chronic non-specific low-back pain (NSLBP) in the short term. Strong evidence exists for the use of an aqueous Harpagophytum extract at a daily dose equivalent of 50 mg harpagoside in the treatment of acute exacerbations of chronic NSLBP.

Preparations from devil's claw differ in their content of active ingredients as assessed by the quantity of harpagoside present. The harpagoside content in the daily dose of Doloteffin (extraction solvent water) is double that of preparations extracted with 60% ethanol. Only preparations with proven effectiveness for painful lower back or arthrotic pain are an attractive alternative to synthetic analgesics, and are of substantial benefit in the treatment of chronic pain. From an evidence based view, extract with at least 50 mg harpagoside in the daily dose should be recommended for the treatment of pain. Treatment with devil's claw extract is associated with a lower risk of adverse events than treatment with synthetic analgesics, and may contribute in the majority of patients to the relief of pain.

Various preparations from Harpagophytum procumbens are used for the treatment of pain in the joints and lower back. Studies published in peer reviewed journals were examined for their clinical evidence. The studies offering preparations with 50-60 mg harpagoside in the daily dosage are of better quality and provide more reliable evidence on efficacy than a proprietary ethanol extract with half the amount of harpagoside per day. However, confirmatory studies are required for all extracts before they can gain a place in treatment guidelines.