Adrenergic bronchodilators

Adrenergic bronchodilators (specifically beta2-adrenoreceptor agonists) dilate the bronchi by a direct action on the beta2-adrenoreceptors on the bronchial smooth muscle and relax the muscle.

There are two categories of beta2-adrenoreceptor agonists used in asthma. The short acting adrenergic bronchodilators are used on an as needed basis to control symptoms of asthma. The longer acting bronchodilators are used regularly, twice daily, as adjunct therapy in patients whose asthma is poorly controlled by inhaled corticosteroids.