The integrity of the chemical and physical structure of the horny layer is essential for maintaining the skin in good health. Any disturbance of this integrity may lead to cutaneous reactions of varying degree: dryness, redness, inflammation. The measurement of Transepidermal Water Loss (TEWL) allows one to record this kind of disturbance and to follow the slow return to normal. In this in vivo study two techniques of insulting the epidermis were used: stripping and washing with sodium lauryl sulfate (SLS). A significant increase of TEWL values resulted in both cases. The application of emulsions containing 0.5% and 1% of a synthetic ceramide type-2 (N-stearoyl-DL-erythro-sphinganine) decreased the disturbance measured by TEWL, in a significant fashion in both trials. The placebo emulsions showed no significant effect. The ceramide thus seemed to participate in the restructuring of the horny layer.