Abstract: Harpagophytum procumbens subsp. procumbens (Burch.) DC. ex Meisn. (Sesame seed Family— Pedaliaceae) is a popular medicinal plant known as Devil’s claw. It is predominantly distributed widely over southern Africa. Its impressive reputation is embedded in its traditional uses as an indigenous herbal plant for the treatment of menstrual problems, bitter tonic, inflammation febrifuge, syphilis or even loss of appetite. A number of bioactive compounds such as terpenoids, iridoid glycosides, glycosides, and acetylated phenolic compounds have been isolated. Harpagoside and harpagide, iridoid glycosides bioactive compounds have been reported in countless phytochemical studies as potential anti-inflammatory agents as well as pain relievers. In-depth studies have associated chronic inflammation with various diseases, such as Alzheimer’s disease, obesity, rheumatoid arthritis, type 2 diabetes, cancer, and cardiovascular and pulmonary diseases. In addition, 60% of chronic disorder fatalities are due to chronic inflammatory diseases worldwide. Inflammation and pain-related disorders have attracted significant attention as leading causes of global health challenges. Articles published from 2011 to the present were obtained and reviewed in-depth to determine valuable data findings as well as knowledge gaps. Various globally recognized scientific search engines/databases including Scopus, PubMed, Google Scholar, Web of Science, and ScienceDirect were utilized to collect information and deliver evidence. Based on the literature results, there was a dramatic decrease in the number of studies conducted on the anti-inflammatory and analgesic activity of Devil’s claw, thereby presenting a potential research gap. It is also evident that currently in vivo clinical studies are needed to validate the prior massive in vitro studies, therefore delivering an ideal anti-inflammatory and analgesic agent in the form of H. procumbens products.
Conclusion : Harpagophytum procumbens is a highly valued medicinal plant in southern Africa as well as the entire world. The body of evidence has shown that Devil’s claw plants are richly endowed with anti-cholesterolemic, antioxidant, anti-inflammatory, and pain killing effects for the therapeutic treatment of countless diseases including rheumatoid arthritis, memory loss, lower back pain, osteoarthritis, lumbago, Syphilis, diabetes, indigestion, and heartburn, as well as acting as a detoxifying and tonic agent. Toxicological data have shown that H. procumbens has adverse effects in high concentrations and various models promote low dose levels as a safety parameter. Despite the massive body of evidence of in vivo studies on the anti-inflammatory and analgesic activity of H. procumbens, alternative lines for future studies focus on animal and human models. Due to its popularity, Devil’s claw has been well-documented since the 1800 s, nonetheless, the research data on the anti-inflammatory and analgesic activity of H. procumbens has reduced since the 2000 s. However, this review has identified the decline in research data and promotes further investigation regarding the above. In order to streamline the future application of H. procumbens, more clinical studies are required to close the gap in research. Hence, providing increased therapeutic efficacy and safer H. procumbens products in the health and pharmaceutical sectors.
Keywords: Devil’s claw; Harpagophytum procumbens; clinical studies; anti-inflammatory; analgesic
The Fight against Infection and Pain: Devil’s Claw (Harpagophytum procumbens) a Rich Source of Anti-Inflammatory Activity: 2011–2022, Nomagugu Gxaba, Molecules 2022, 27, 3637.

Abstract : 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.
A Review of the Biological and Potential Therapeutic Actions of Harpagophytum procumbens, L. Grant, Phytother. Res. 21, 199–209 (2007)

Abstract
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 max 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
Harpgophytum procumbens for osteoarthritis and low back pain: A systematic review, Joel J Gagnier, BMC Complementary and Alternative Medicine