Teaching chronic obstructive airway disease patients using a metered-dose inhaler

Asthma and chronic obstructive airway disease ,（COAD） are chronic inflammatory disorders of the airways which are usually associated with widespread airway obstruction that is often relieved by treatment. β2-adrenoreceptor agonists and corticosteriods are the mainstay of the management of this disease. The preferred route of administration of these agents is by inhalation. This allows the drug to be delivered directly to the airway with more rapid relief and fewer side effects than systemic route. The main disadvantage of metered-dose inhaler （MDI） use is that the correct use requires good technique;