Devil's Claw Research Articles

Isolation and Anti-Inflammatory Activity Evaluation of Triterpenoids and a Monoterpenoid Glycoside fromHarpagophytum procumbens

A new triterpenoid glycoside, designated harproside (1), and a new iridoid glycoside, named pagide (2), along with six known triterpenoids (3-8), were obtained from the tubers of Harpagophytum procumbens D. C. (devil's claw), and their structures were established through chemical methods and spectroscopic analyses. In an in vitro assay, the six triterpenoids showed anti-inflammatory activity. Compounds 3, 7, and 8 showed significant inhibitory activity against neutrophil respiratory burst stimulated by PMA, while compounds 4, 5, and 6 showed marginal inhibitory activity.

QUALITY AND TOXICITY STUDY ON DEVIL\'S CLAW CAPSULES MARKETED IN SAUDIA ARABIA

Devil's Claw is used in osteoarthritis; rheumatoid arthritis, diabetes, indigestion and heartburn. The tuber is mostly used as remedy for gall, liver, kidney and bladder problems; but western herbalists sell them mostly in the treatment of rheumatic pain, gout and joint problems, mainly arthrits and lumbago. Devil's Claw may also be used as a lymphatic system stimulant to help detoxify the entire body. It has a cooling energy with bitter and astringent tastes, and is considered an alterative, anti-inflammatory and analgesic herb for low back pain. Devil's claw treatment in this study showed no alarming signs and symptoms of toxicity during the current acute, sub-acute and chronic toxicity studies both in male and female mice as well as in female rats as second animal model. The signifieant decrease in urie aeid levels (p < 0.01) in the serum of treated animals may be attributed to some Devil's claw chemical constituents. Precautions for prolonged use of Devil's claw should be taken into consideration, so that the body uric acid levels remair. within the normal range.

Evolutionary divergence of field and laboratory populations of Manduca sexta in response to host‐plant quality

1. The tobacco hornworm, Manduca sexta, has been an important model system in insect biology for more than 50 years. In nature, M. sexta successfully utilises a range of host plants that vary in quality. The consequences of laboratory domestication and rearing on artificial diet for fitness of phytophagous insects on natural host plants have not been explored.2. We examine the evolutionary divergence of two domesticated laboratory populations and a field population (separated for more than 40 years, or &gt; 250 laboratory generations) of M. sexta with respect to performance and fitness on two natural host plants: a typical host plant, tobacco (Nicotiana tabacum) and a novel host plant, devil's claw (Proboscidea louisianica).3. For both field and laboratory populations, rearing on devil's claw resulted in animals with lower survival, smaller final size, longer development time, and reduced size‐corrected fecundity than animals reared on tobacco. Reductions in some fitness components (survival and fecundity) were greater for the laboratory population animals than the field population animals.4. When reared on tobacco, the laboratory population animals had similar or larger pupal masses and slightly shorter development times than when reared on artificial diet, suggesting that laboratory domestication on artificial diet has not greatly affected the ability of M. sexta to perform well on a typical natural host plant.5. Although field and laboratory populations exhibited qualitatively similar responses to host‐plant quality, i.e. reduced performance on devil‘s claw, the magnitude of this reduction differed across populations, with the domesticated laboratory populations having greater reductions in performance than the field population. The use of domesticated populations as models for responses of field populations may therefore be more appropriate for considering environmental conditions that are relatively benign or near‐optimal, than when exploring responses to extreme or stressful conditions.

Inhibitory effects of devil’s claw (secondary root of Harpagophytum procumbens) extract and harpagoside on cytokine production in mouse macrophages

Successive oral administration (50 mg/kg) of a 50% ethanolic extract (HP-ext) of devil's claw, the secondary root of Harpagophytum procumbens, showed a significant anti-inflammatory effect in the rat adjuvant-induced chronic arthritis model. HP-ext dose-dependently suppressed the lipopolysaccharide (LPS)-induced production of inflammatory cytokines [interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha)] in mouse macrophage cells (RAW 264.7). Harpagoside, a major iridoid glycoside present in devil's claw, was found to be one of the active agents in HP-ext and inhibited the production of IL-1beta, IL-6, and TNF-alpha by RAW 264.7.

Screening pharmaceutical preparations containing extracts of turmeric rhizome, artichoke leaf, devil's claw root and garlic or salmon oil for antioxidant capacity.

Pharmaceutical preparations derived from natural sources such as vegetables often contain compounds that contribute to the antioxidant defence system and apparently play a role in the protection against degenerative diseases. In the present study, commercial preparations containing extracts of turmeric, artichoke, devil's claw and garlic or salmon oil were investigated. The products were divided into fractions of different polarity, and their antioxidant activity was determined using the Trolox equivalent antioxidant capacity (TEAC) assay. This test is based on the efficacy of the test material to scavenge 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) derived radicals. Total phenols were determined in all fractions as well as specific carotenoids in the most lipophilic fraction to assess their contribution to the antioxidant activity. For comparison, the radical scavenging effect of selected constituents of the extracts such as curcumin, luteolin, kaempferol, chlorogenic acid, harpagoside, beta-carotene and alpha-tocopherol was investigated and compared with that of Trolox. Curcumin, luteolin, kaempferol, chlorogenic acid and beta-carotene showed an antioxidant activity superior to Trolox in the TEAC assay; harpagoside was barely active. All fractions of the turmeric extract preparation exhibited pronounced antioxidant activity, which was assigned to the presence of curcumin and other polyphenols. The antioxidant activity corresponding to the artichoke leaf extract was higher in the aqueous fractions than in the lipophilic fractions. Similarly, devil's claw extract was particularly rich in water-soluble antioxidants. Harpagoside, a major compound in devil's claw, did not contribute significantly to its antioxidant activity. The antioxidant capacity of the garlic preparation was poor in the TEAC assay. That of salmon oil was mainly attributed to vitamin E, which is added to the product for stabilization. In all test preparations, the antioxidant activity was significantly correlated with the content of total phenolic compounds.

Fitness consequences of host plant choice: a field experiment

Determining the relative contributions of different ecological factors for herbivore fitness is one key to understanding the ecology and evolution of host plant choice by herbivores. Natural enemies are increasingly being recognized as an important factor: host plants of inferior quality for development may still be used by herbivores if they provide enemy-free space (EFS). Here we used the tobacco hornworm, Manduca sexta, to experimentally disentangle the effects of natural enemies from the potentially confounding factors of host plant quality, competition and microhabitat. We explored the consequences for both individual components of fitness and total fitness of M. sexta feeding on a typical high quality host plant, tobacco Nicotiana tabacum and a novel, low quality host plant, devil's claw Proboscidea louisianica in an experimental field environment in the presence of a parasitoid natural enemy, Cotesia congregata. Although early larval survival, development and growth rates, final body size and fecundity were all reduced for M. sexta feeding on devil's claw, a high rate of parasitism on tobacco and an absence of parasitism on devil's claw contributed to similar total fitness (net reproductive rate, R 0 ,) across the two host plant species. Our results suggest M. sexta has adopted a novel host plant (devil's claw) outside its typical host range because this host plant provides enemy free space. In addition, oviposition behavior of adult female M. sexta appears to be well suited to exploiting the enemy-free space on devil's claw; oviposition by M. sexta on devil's claw appears to correspond with seasonal variation in parasitoid abundance.

Antioxidant Activity and Bioactive Constituents of the Aerial Parts of Harpagophytum Procumbens Plants

ABSTRACTHarpagophytum procumbens is an herbaceous plant with high medicinal value that grows in the Kalahari Desert region of Africa. Devil's claw plant tubers have been used since time immemorial by the native population of Southern Africa for treating a huge number of human ailments, including fever, diabetes, diarrhea and blood diseases. More recently, extracts of the secondary roots of the species have been found to be effective in the treatment of degenerative rheumatoid arthritis, osteoarthritis, tendonitis, kidney inflammation and heart disease. Therefore, Harpagophytum procumbens has been increasingly considered an alternative to non-steroidal anti-inflammatory drugs. The antioxidant activities of pure metabolites, as well as of total methanol extracts of the Devil's claw plants were evaluated in 2,2′-diphenyl-1-picrylhydrazyl (DPPH·), oxygen radical absorbance capacity (ORACFL) and hydroxyl radical averting capacity (HORACFL) assays. The crude methanolic extract may be attractive for various commercial purposes since it displayed antioxidant activity and it can be conveniently and economically prepared.

Evidence of Effectiveness of Herbal Medicinal Products in the Treatment of Arthritis

Herbal medicinal products (HMPs) are used in a variety of oral and topical forms for the treatment of osteoarthritis. The aim of this study was to update a previous systematic review published in 2000. We searched electronic databases (MEDLINE, EMBASE, CISCOM, AMED, CINAHL, Cochrane registers) to June 2007, unrestricted by date or language, and included randomized controlled trials that compared HMPs with inert (placebo) or active controls in patients with osteoarthritis. Five reviewers contributed to data extraction. Disagreements were discussed and resolved by consensus with reference to Cochrane guidelines and advice from the Cochrane Collaboration.Thirty-five studies (30 studies identified for this review update, and 5 studies included in the original review) evaluating the effectiveness of 22 HMPs were included. However, due to differing HMPs, interventions, comparators, and outcome measures, meta-analysis was restricted to data from studies of three HMPs: topical capsaicin, avocado-soybean unsaponifiables, and the Chinese herbal mixture SKI306X showed benefit in the alleviation of osteoarthritic pain.Several studies investigating products from devil's claw, and a powder from rose hip and seed, reported favorable effects on osteoarthritic pain, whereas two studies of a willow bark extract returned disparate results. Three studies of Phytodolor N(R) were of limited use because doses and measures were inconsistent among trials. The remaining single studies for each HMP provided moderate evidence of effectiveness. No serious side effects were reported with any herbal intervention.Despite some evidence, the effectiveness of none of the HMPs is proven beyond doubt. The obvious potential benefits of HMPs in the treatment of osteoarthritis are reduced reliance on synthetic medications with the associated risks of harmful adverse events, but further clinical trials are necessary before HMPs can be adopted in osteoarthritis treatment guidelines.

Neuroprotective and antiinflammatory effects of extracts from in vitro cultivated Harpagophytum procumbens (devil's claw)

Harpagophytum procumbens, known as devil's claw, has been used traditionally for the treatment of pain, fevers, and dyspepsia. Recently, it has become popular for the treatment of rheumatoid and osteoarthritis. Most of the world's supply comes from Namibia, with lesser amounts from South Africa and Botswana. In 2002, the peak year of export, 1,018 tonnes of dried tubers were exported from southern Africa, representing the harvest of millions of plants. In 2000, recommendations were made to the Convention on the International Trade in Endangered Species (CITES) to add devil's claw to Appendix II. In 2004, the proposal was formally withdrawn due to the efforts of the range states to address sustainability issues. The governments of the main range states are working with local communities to develop policies and regulations to protect the species and to determine a sustainable harvest [1].

Effects of Devil's Claw (Harpagophytum procumbens) on the multidrug transporter ABCB1/P-glycoprotein

Devil's Claw (Harpagophytum procumbens) a plant native to Southern Africa, has historically been used in traditional medicine to treat a wide range of diseases and currently is widely employed as anti-inflammatory and pain-relieving natural remedy in Europe and other parts of the world. Little is known about possible herb-drug interactions arising from effects of Devil's Claw on the major drug metabolizing enzymes or transporters. This study evaluated in vitro the effects of Devil's Claw on the multidrug transporter ABCB1/P-glycoprotein. The effects of three commercially available Devil's Claw preparations and that of pure harpagoside were studied in the human kidney (HK-2) proximal tubule cell line, constitutively expressing ABCB1/P-glycoprotein (P-gp). Pgp activity and expression were tested by the calcein-AM test and by Western blotting, respectively. Commercial preparations inhibited P-gp activity, even if to a different extent, while pure harpagoside was almost ineffective. In cells cultured for three days in the presence of Devil's Claw preparations or pure harpagoside, a dose-dependent P-gp upregulation was found. Our results demonstrate for the first time that Devil's Claw may interact with the multidrug transporter ABCB1/P-gp, the effect not appearing strictly related to the harpagoside relative content. Modulation of both P-gp activity and P-gp expression by Devil's Claw raise the possibility of herb-drug interactions, to be further explored in depth.

Regression of follicular lymphoma with alternative therapy using Devil's Claw (DC); Coincidence or causation?

e19560 Background: Alternative therapies are used by c 30% of cancer pts (Ernst and Cassileth, Cancer 2000). Two follicular lymphoma (FL) pts who had objective tumor regression after taking the herb DC without cytotoxic therapy are reported here. Methods: This was a retrospective chart review. In January 2000, pt #1 presented with co-existent IgG plasma cell dyscrasia and stage 3A grade 2 FL with 5 cm cervical and R/P nodes. CT scan 10 months later showing partial regression of adenopathy. On enquiry, he was taking DC and Essiac. He developed overt myeloma in Aug 2001, when he stopped DC/Essiac and received HDCT/ASCT following which there has been no clinical progression of lymphoma. In November 2003, pt #2 presented with stage 3A grade 1 FL. CT scan showed widespread adenopathy (2.5 cm max.). He learned of pt #1 through the local Lymphoma Patient Support Group and started DC alone. CT scan 11 months later showed decreased adenopathy and splenomegaly which has been sustained. Results: CT images at baseline and follow-up confirm objective regression. Conclusions: DC (Harpagophytum procumbens) tuberous root contains Harpagoside and Beta sitosterol and has anti-inflammatory properties probably by suppressing COX-2 and iNOS expression (Jang et al, J Pharmacol Sci, 2003). There is good evidence for its use in osteoarthritis ( http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-devilsclaw.html ) but it has not been reported to have anticancer activity. COX-2 inhibition has an accepted role in cancer prevention (Steinbach et al, NEJM 2000), has been implicated in lymphomagenesis (Wun et al, Leuk Res 2004) and associated with both stage of lymphoma and response to standard treatment (Hazar et al, Leuk Lymphoma 2004). However, spontaneous regression in low grade lymphoma has been reported in 7 of 44 pts on observation only (Krikorian et al, 1980); none were on herbal medications or COX-2 inhibitors. The key issue in both these patients is whether or not the disease regression was “spontaneous” or causally related to DC therapy, but the timing of response suggests a potential therapeutic benefit. Considering the role of COX-2 inhibitors and the relation between components of DC and COX-2, further investigation is warranted, preferably with a COX-2 inhibitor of known purity. No significant financial relationships to disclose.

Too much effectiveness from a herbal drug

Herbal drugs may be useful in the control of pain, especially when associated with rheumatic diseases, inflammatory conditions, headache and dysmenorrhoea. These remedies usually exert their activity on mild–moderate pain, with a delayed onset of the analgesic effect; herbal drugs might also be useful in pain prevention (e.g. in headaches), but they are not usually very effective in the management of acute pain. Among most studied analgesic herbs are Devil's Claw (Harpagophytum procumbens), Feverfew (Tanecetum parthenium) and Chaste tree (Vitex agnus castus). The product PC.28 PLUS, containing a combination of these three herbs, was marketed by the Italian company Cosval (Arese, Italy) with the indication ‘For headache, painful joints and painful menstrual cycle’; the label on the drug's box also stated ‘Natural innovative products’. Declared components of each tablet were: T. parthenium 0.5% in parthenolides 120 mg (total parthenolides per tablet 0.06 mg), V. agnus castus 0.5% in agnucastosides 80 mg (total agnucastosides per tablet 0.04 mg), and H. procumbens 20 mg (no reference to harpagosides). The product also contained magnesium, vitamin E and vitamin B6. Several informative reports were received by the pharmacovigilance and phytovigilance system of the Florence University Medical School and the Centre for Natural Medicine of Local Health Service of Empoli (ASL 11, Florence, Italy) by patients who attributed a very high effectiveness to the product in the treatment of headache and menstrual pain. One or two tablets (even sublingually) at pain onset were rapidly effective, often with complete suppression of pain. Since high effectiveness and very rapid onset appeared suspicious in view of the extremely low doses of active compounds reported by the producer, we decided to analyse the product to assess the possible presence of synthetic drugs. Tablets were analysed by means of a high-performance liquid chromatography–mass spectrometry system (Varian 500-MS LC Ion Trap; Varian, Inc., Palo Alto, CA, USA). A peak compatible with the anti-inflammatory drug nimesulide was identified in the output (Figure 1a) and the characterization of the drug was confirmed by fragmentation analysis (Figure 1b). The concentration of nimesulide was 50 mg per 1000 mg of product (about 20.5 mg per tablet). Since the dosage of PC.28 PLUS suggested by the producer was one to two tablets per day, a daily dose was therefore 20–41 mg nimesulide. Some patients reported taking up to four to five tablets per day, since the product was considered natural and safe. It should be noted that nimesulide is the most used anti-inflammatory/analgesic drug in Italy, and can be dispensed only after a medical prescription. Nimesulide was recently reviewed by the Italian Ministry of Health following several reports of lethal and life-threatening side-effects [1]. The finding of nimesulide contamination was further confirmed by analyses conducted in a different laboratory on tablets from different batches. The producer subsequently decided to recall PC.28 PLUS, stating that an internal analysis had shown contamination with nimesulide ‘in traces’, probably due to the presence of the drug in one of the herbs’ stocks; the Italian Ministry of Health also ordered product withdrawal from the market. Figure 1 HPLC/MS analysis of the product. A peak compatible with the anti-inflammatory drug nimesulide was identified in the output (a) and the characterization of the drug was confirmed by fragmentation analysis (b) The three natural products contained in PC.28 PLUS may have some analgesic/anti-inflammatory effects [2–6], but the concentrations in the tablets were extremely low. In conclusion, pharmacovigilance and phytovigilance deal with the identification of ‘signal alarms’. These usually derive from spontaneous reports of adverse drug reactions or lack of efficacy of certain drugs. In the field of herbal medicine, it appears that the report of an unusually high therapeutic effect might also be an important signal alarm. We therefore encourage clinicians to report to pharmacovigilance systems adverse reactions to herbal drugs, but also unexpected high efficacy or any therapeutic effect not in keeping with the pharmacodynamics and pharmacokinetics of herbal drugs active compounds.

Retrospective evaluation of biopsychosocial determinants and treatment response in patients receiving devil's claw extract (doloteffinR)

In a retrospective evaluation of patients taking part for 2 months in a postmarketing surveillance study on the effectiveness and safety of Harpagophytum procumbens, associations were found to known explanators of pain, disability and depression. Therefore, treatment non-responders might best be referred to a multimodal pain relief program that deals with fear avoidance beliefs, enhances experiences that decrease perceptions linking disability and pain and forces the patients to rethink the way they deal with the problem. However, during treatment with the aqueous Harpagophytum extract, this decision might reasonably be postponed to the end of month 4, since it has been shown that the maximum pain relief occurs after 3-4 months.

The Inhibition of Free Radical Generation by Preparations of Harpagophytum procumbens in vitro

Harpagophytum procumbens (Hp), commonly known as Devil's Claw has been used as a traditional treatment for a variety of illnesses for centuries. Since the early twentieth century, it has become a popular antiinflammatory and analgesic preparation amongst European herbalists for supportive or adjuvant treatment of degenerative joint diseases. Extracts of Hp tubers have demonstrated antiinflammatory and analgesic effects in animal models of inflammation and in human trials. The mechanism(s) of action responsible for these attributes, however, remain to be elucidated. Reactive oxygen species generated in acute and chronic inflammatory diseases are known to be cytotoxic and can cause tissue damage. In this study, a root tuber extract (Hp extract) and commercially available tincture (Hp tincture) were investigated for antioxidant characteristics using in vitro test systems. Both preparations were found to effectively scavenge DPPH radical, inhibit nitrite levels in supernatants harvested from LPS-stimulated RAW 264.7 macrophages, and cause dose-dependent suppressions in the detection of fMLP- and AA-induced neutrophil MPO. The antioxidant effects demonstrated for both preparations of Hp may contribute to the antiinflammatory and analgesic properties observed for the plant.

QUALTY CONTROL OF FOUR FINISHED HERBAL DRUG FORMULATIONS MARKEDTED IN SAUDIA ARABIA

Quality control of the main constituents was conducted on four finished herbal drug products, one-batch each in soft gelatin capsules manufactured by an American Company including Devil's claw, Valerian, Twinlab powerman Yohimbe power and Korean white Ginseng root. Pharmacopoeial constants and elemental analysis were determined. The results obtained revealed that there is no significant difference from the constants published in different Compendia. The results indicated no adulteration or substitution in these herbal preparations, and no pesticidal residues were detected in all samples under investigation. The results of viable count revealed that all the four herbal preparations were free from pathogenic organisms and the limits of aerobic and yeast not exceed the acceptable limits. The results obtained for the detection of aflatoxins revealed that the fungi isolated from the four herbal preparations showed no fluorescence in UV after growing on Sabauraud medium, the chloroform extracts of the four preparations when subjected to HPLC analysis, confirmed absence of aflatoxins. The obtained Pharmacopoeial values are around the recorded values. HPLC, qualitative and quantitative determinations of the major constituents were in agreement with the reported data.

Metabolite and hormonal status of hairy root cultures of Devil's claw ( Harpagophytum procumbens) in flasks and in a bubble column bioreactor

Hairy root cultures of Devil's claw ( Harpagophytum procumbens), a plant with high medicinal value due to its bioactive metabolites, were cultivated in two different ways: (1) in conventional flasks with shaking and (2) in a 3-l bubble column bioreactor. We investigated parts of the metabolite profiles of both of these types of culture and identified the iridoid glycosides harpagide and harpagoside by HPLC analysis. The bioreactor cultures contained more harpagide than the flask cultures. In addition, several cinnamic acid derivatives, amino acids, sugars, phytosterols and carotenoids were identified as minor compounds of the Harpagophytum hairy roots by GC–MS analysis. A comparison between the flask and bioreactor cultures revealed both qualitative and quantitative differences in some major metabolites. The bioreactor cultures had higher levels of sugars and amino acids, probably due to their better nutrient status. Determination of the hormonal status of the cultures showed that the free indole-3-acetic acid content was similar in the two cultures, but the level of indole-3-acetic acid conjugates was higher in the shake-flasks than in the bioreactor cultures. Levels of abscisic acid, salicylic acid, and aminocyclopropane carboxylic acid were also significantly higher (and levels of jasmonic acid were very variable and non-significantly higher) in the shake-flask cultures. These findings are discussed with respect to relative stress levels in the two culture systems and the scope for using them for secondary metabolite production.

Effectiveness and safety of Devil's Claw tablets in patients with general rheumatic disorders

Arthritis and other rheumatic conditions (AORC) are the leading cause of disability, are associated with poor quality of life and incur considerable direct and indirect costs. It is considered that the instance of AORC will continue to increase. To assess the effectiveness, safety and tolerability of Harpagophytum (Bioforce) in the treatment of AORC, a single group open study of 8 weeks duration (259 patients) was performed in the United Kingdom. Effectiveness was assessed by numeric rating scales, the Western Ontario and McMasters Universities Osteoarthritis (WOMAC) Index and the Algofunctional Hand Osteoarthritis Index. Tolerance was measured by a numeric rating scale and safety by self-reporting, blood analysis and liver function tests. Quality of life was measured by SF-12 questionnaire. There were statistically significant (p < 0.0001) improvements in patient assessment of global pain, stiffness and function. There were also statistically significant reductions in mean pain scores for hand, wrist, elbow, shoulder, hip, knee and back pain. Quality of life measurements (SF-12) were significantly increased from baseline and 60% patients either reduced or stopped concomitant pain medication. Harpagophytum is an effective and well-tolerated serious treatment option for mild to moderate degenerative rheumatic disorders providing improved quality of life measure.

A Review of the Efficacy and Safety of Devil's Claw for Pain Associated With Degenerative Musculoskeletal Diseases, Rheumatoid, and Osteoarthritis

Harpagophytum procumbens, known as devil's claw, has been used traditionally for the treatment of pain, fevers, and dyspepsia. Recently, it has become popular for the treatment of rheumatoid and osteoarthritis. Studies have yet to establish a clear mechanism of action; however, current research is focusing on pro-inflammatory mediators as well as on potential antioxidant characteristics.

A review of the biological and potential therapeutic actions of Harpagophytum procumbens

Harpagophytum procumbens (Hp), commonly known as Devil's Claw is a perennial plant which thrives in arid conditions. For centuries, it has been used as a traditional treatment for a variety of illnesses, including fevers, skin complaints, arthritis and diseases of the digestive tract as well as an appetite stimulant. Since its introduction to Europe in the early twentieth century, it has become a popular antiinflammatory and analgesic preparation amongst herbalists for supportive or adjuvant treatment of degenerative joint diseases, tendonitis, headache, backache and menstrual pain. The validity of Hp as an effective antiinflammatory and analgesic preparation, particularly in the relief of arthritic symptoms, has been investigated in numerous animal, clinical and in vitro studies. Although some contradictory evidence exists, the majority of animal studies appear to indicate Hp as an effective antiinflammatory and analgesic preparation in the treatment of acute and subacute inflammation. Clinical trials support Hp as a beneficial treatment for the alleviation of pain and improvement of mobility in a variety of musculoskeletal conditions. Analysis of the in vitro and ex vivo studies that currently exist, indicate that Hp has significant effects on numerous proinflammatory markers. However, the exact mechanism(s) by which Hp may reduce inflammation remain to be elucidated.

Devil's Claw (Harpagophytum procumbens) as a Treatment for Osteoarthritis: A Review of Efficacy and Safety

Osteoarthritis (OA) is a highly prevalent musculoskeletal disorder. Conventional treatment (i.e., the use of nonsteroidal anti-inflammatory drugs-NSAIDs) is associated with well-documented adverse effects. Devil's Claw (Harpagophytum procumbens) a traditional South African herbal remedy used for rheumatic conditions, may be a safer treatment option. To date, 14 clinical trials have assessed its efficacy/ effectiveness in OA. To address the two main questions of importance to clinicians: (1) Does Devil's Claw work for the treatment of OA, and (2) Is it safe? A review of the literature on Devil's Claw and OA from 1966 to 2006 was performed using multiple search databases, monographs, and citation tracking. Relevant trials in all languages were identified and included. Both internal validity (i.e., adequacy of the dosage and period of treatment for this condition, reporting of randomization, rates of dropout, blinding, and statistical analysis) and external validity (i.e., inclusion/ exclusion criteria, baseline characteristics of the study populations, trial setting, and the appropriateness of the outcome measures of the trials) were assessed. Fourteen studies were identified: eight observational studies; 2 comparator trials (1 open, the other randomized to assess clinical effectiveness); and 4 double-blinded, placebo-controlled, randomized controlled trials to assess efficacy. Many of the published trials lacked certain important methodological quality criteria. However, the data from the higher quality studies suggest that Devil's Claw appeared effective in the reduction of the main clinical symptom of pain. The assessment of safety is limited by the small populations generally evaluated in the clinical studies. From the current data, Devil's Claw appears to be associated with minor risk (relative to NSAIDs), but further long-term assessment is required. The methodological quality of the existing clinical trials is generally poor, and although they provide some support, there are a considerable number of methodologic caveats that make further clinical investigations warranted. The clinical evidence to date cannot provide a definitive answer to the two questions posed: (1) Does it work? And (2) is it safe? A definitive high-quality trial that addresses the necessary methodologic improvements noted is needed to answer these important clinical questions.