Abstract: The present invention provides a stable pharmaceutical composition to be used with pressurized metered dose inhalers and comprises a ?2 agonist, a propellant, a co-solvent, an organic acid(s) and optionally water. The invention further provides stable pharmaceutical composition comprising ?2 agonist, an inhaled corticosteroid and/or a long acting muscarinic antagonist. The invention also provides pharmaceutical composition for the treatment or prophylaxis of asthma, chronic obstructive pulmonary disease (COPD), rhinitis or as adjunct therapy for cystic fibrosis, non-cystic fibrosis bronchiectasis, lung infections or pulmonary fibrosis.