Arnica / Urtica urens lotion

Arnica L. genus (Asteraceae) comprises perennial herbs native to the temperate and boreal parts of the northern hemisphere. Arnica montana is the main species. It shows different biological activities, such as antioxidant, anti-inflammatory, antibacterial, antifungal, and antitumor effects. The Arnica formulations are mainly used for pain management. This systematic review is aimed at summarizing the studies focusing on the use of Arnica products on pain and inflammatory signs due to traumatic injuries related to sport and surgical interventions as well as to arthritis and other inflammatory conditions. Both phytotherapeutic and homeopathic formulations are taken into account. This paper only includes manuscripts published in mainstream journals. A literature search from Scopus, Web of Science, and PubMed databases has been carried out using a combination of the keywords “Arnica”, “trauma”, “sport”, “injury”, “injuries”, and “pain”. According to the search strategy and inclusion criteria for this study, 42 eligible papers, focusing on both Arnica alone and formulations containing a mixture of plant extracts, have been finally selected. This review critically discusses the in vitro, in vivo, and clinical studies dealing with Arnica products, reporting both positive and negative outcomes, thus providing perspectives for future research on the plant pharmacological potential.

Abstract licence: CC BY 4.0

Background:HomeopathicArnica montanais used in surgery as prevention or treatment for the reduction of pain and other sequelae of surgery. Our aim was to perform a metaanalysis of clinical trials to assess efficacy ofArnica montanato reduce the inflammatory response after surgery.Method:We conducted a systematic review and metaanalysis, following a predefined protocol, of all studies on the use of homeopathicArnica montanain surgery. We included all randomized and nonrandomized studies comparing homeopathicArnicato a placebo or to another active comparator and calculated two quantitative metaanalyses and appropriate sensitivity analyses. We used “Hegde's g,” an effect size estimator which is equivalent to a standardized mean difference corrected for small sample bias. The PROSPERO registration number is CRD42020131300.Results:Twenty-three publications reported on 29 different comparisons. One study had to be excluded because no data could be extracted, leaving 28 comparisons. Eighteen comparisons used placebo, nine comparisons an active control, and in one caseArnicawas compared to no treatment. The metaanalysis of the placebo-controlled trials yielded an overall effect size of Hedge's g = 0.18 (95% confidence interval −0.007/0.373;p= 0.059). Active comparator trials yielded a highly heterogeneous significant effect size of g = 0.26. This is mainly due to the large effect size of nonrandomized studies, which converges against zero in the randomized trials.Conclusion:HomeopathicArnicahas a small effect size over and against placebo in preventing excessive hematoma and other sequelae of surgeries. The effect is comparable to that of anti-inflammatory substances.

Abstract licence: CC BY 4.0