A Meta-Analysis of Randomized, Placebo-Controlled Clinical Trials of Efamol® Evening Primrose Oil in Atopic Eczema. Where Do We Go from Here in Light of More Recent Discoveries?

N.   L.   Morse; P.   M.   Clough

Abstract

The global incidence of atopic eczema is escalating. While new treatment options are becoming available, previous treatments with certain confirmed benefits are still worth investigating as safe and effective therapies. One such treatment, Efamol® evening primrose oil (EPO), was proven efficacious in a 1989 meta-analysis of randomized, doubleblind, placebo-controlled clinical trials. A decade of further testing and subsequent independent reanalysis of 26 clinical studies including 1207 patients presented here, establishes that Efamol® EPO has a simultaneous, beneficial effect on itch/pruritis, crusting, oedema and redness (erythema) that becomes apparent between 4 and 8 weeks after treatment is initiated. However, the magnitude of this effect is reduced in association with increasing frequency of potent steroid use. This and other confounding variables that are now being reported in the literature may account for historically reported inconsistent patient response. Recent research has uncovered unique complexities in fatty acid metabolism and immune response in the atopic condition beyond those previously reported and may well have identified a subcategory of nonresponders and has helped established those that can consistently derive significant benefit. Further research is needed to provide a better understanding of the physiology behind this complex disorder and the beneficial role that fatty acids can play in its development and management. Conclusion: Efamol® EPO has a simultaneous, beneficial effect on itch/pruritis, crusting, oedema and redness (erythema) that becomes apparent between 4 and 8 weeks after treatment is initiated. However, the magnitude of this effect is reduced in association with increasing frequency of potent steroid use.

Keywords: Atopic eczema, atopic dermatitis, evening primrose oil (EPO), gamma-linolenic acid (GLA), skin, Efamol, metaanalysis, efficacy of evening primrose oil (EPO)