The ACVD task force on canine atopic dermatitis (XXIII): are essential fatty acids effective?

Essential fatty acids (EFAs) exhibit the potential to affect allergic infla mmation through the modulation of prostaglandin and leukotriene production, the inhibition of cellular activation and cytokine secretion as well as th e alteration of the composition and function of the epidermal lipid barrier . Because of these multi-facetted effects, EFA have been proposed for treat ment of canine atopic dermatitis (AD) since 1987. To date, more than 20 tri als have been performed, reporting the efficacy of either oral EFA suppleme nts or EFA-rich diets. Unfortunately, most of these studies were found to e xhibit one or more of the following deficiencies: heterogeneity of diagnose s used as inclusion criteria, short duration of supplementation, lack of ra ndomization of treatment allocation, lack of blinding of investigators and/ or owners, lack of placebo or active controls, lack of documentation of pla sma or skin EFA profiles during supplementation, as well as lack of standar dization of the basal diets or supplements which could have provided additi onal EFA. Consequently, there is presently insufficient evidence to recomme nd for or against the use of EFA to control clinical signs of canine AD. Ev idence of efficacy must await the performance of blinded, randomized and co ntrolled trials of at least 3 months duration in which diets are identical for all of study subjects. In these trials, clinical efficacy should be eva luated in relation to plasma and cutaneous EFA treatment-induced alteration s. (C) 2001 Elsevier Science BN. All rights reserved.