A pharmaceutical aerosol formulation suitable for oral and/or nasal inhalation including an anti-inflammatory steroid of the formula in which: R1 is 1-butyl, 2-butyl, cyclohexyl or phenyl and R2 is acetyl or isobutanoyl, in particular ciclesonide. The formulations also include hydrofluorocarbon propellants such as HFC 134a and/or 227, and cosolvent such as ethanol in an amount sufficient to solubilize the ciclesonide or related steroid (and various optional ingredients, such as surfactant). The formulations exhibit very desirable physical and chemical stability, as well as excellent delivery characteristics.