Acne Vulgaris

The free fatty acids have been implicated by indirect evidence in the pathogenesis of acne vulgaris. A determination of the relative irritancy of different chain lengths of these acids therefore assumed major importance. The even numbered free fatty acids from C2to C16were repeatedly applied under occlusive patch tests to human skin. Free fatty acids penetrated the epidermal barrier and produced inflammation. Greater irritancy or penetration or both by the C8to C14range of fatty acids, particularly by the C12fatty acid, was found. Although this study did not reproduce the pathophysiologic conditions that occur in acne vulgaris, the results suggest that the search for differences in the fatty acid spectrum of patients with acne should be focused on the C8to C14range of fatty acids.