Abstract: The present invention provides a propellant-free pharmaceutical formulation and a method for administering the pharmaceutical formulation by nebulizing the pharmaceutical formulation in an inhaler. The propellant-free pharmaceutical formulation comprises: (a) glycopyrronium or a salt thereof; (b) formoterol or a salt thereof; (c) a pharmacologically acceptable stabilizer; (d) a pharmacologically acceptable preservative; and (d) a solvent. Additionally, the present invention provides the use of a combination product comprising glycopyrronium or a salt thereof and formoterol or a salt thereof for the prevention or treatment of chronic obstructive pulmonary disease (COPD) and other respiratory diseases.