The present invention provides a method for optimizing levels of mifepristone in a patient suffering from a mental disorder amenable to treatment by mifepristone. The cosmetic plaster is attached on the one hand, to skin over loose tissues and on the other hand, to skin over firm tissues, preferably adjacent to human bone structure, so that the loose tissue parts are stretched towards the firm tissue parts. The elements and the binder cooperate to refract light incident on a brightness enhancement sheet from a surface on a diffusion sheet side to the other surface in a direction normal to the brightness enhancement sheet.