Deprodone propionate (RD20000) is a corticosteroid which is obtained by esterifying with propionic acid the 17-position of the prednisolone skeleton and deoxidating its 21-position. In Vitro: Deprodone propionate as an effective ingredient, can exhibit its effects to the maximum extent and over a prolonged period of time, do not have skin irritation, and are physicochemically stable. Deprodone propionate can be maintained in a stably suspended state owing to the thickening action of the suspending agent^[1].