Beta2-agonists (bronchodilators) are a group of drugs prescribed to treat asthma.
Short-acting beta-agonists (SABAs) provide quick relief of asthma symptoms. They can also be prescribed to be taken before exercising in order to prevent exercise-induced bronchoconstriction. Short-acting beta-agonists should not be used more than twice a week for shortness of breath. Taking them more often is a sign of poorly controlled asthma. This means you should visit your allergist / immunologist to have your prescription adjusted.
Examples of these short-acting medications include: albuterol (AccuNeb, Proventil HFA, ProAir HFA, Ventolin HFA); levalbuterol (Xopenex, Xopenex HFA) and pirbuterol (Maxair, Maxair Autohaler).
Long-acting beta-agonists (LABAs) are taken on a daily basis to relax the muscles lining the airways that carry air to the lungs. This allows the tubes to remain open, making breathing easier. LABAs should be taken only in combination with a corticosteroid to treat asthma. They are used in a metered-dose or dry powder inhaler.
Combinations of a long-acting beta2-agonist and inhaled corticosteroid include formoterol and budesonide (Symbicort), formoterol and mometasone (Dulera), and salmeterol and fluticasone (Advair).