Pathways of ionic flow through human skin in vivo.

The pathways of electric current have been examined with special electrodes and methods. The results indicate that the flow through ordinary stratified stratum corneum is negligible, and that the dominant ionic path is through the sweat duct units. Here the cells of interest may be oriented perpendicular to the main stratified orientation of the skin, and this may affect the methods and interpretations of absorption/permeability studies.