Bronchodilators are prescribed for a variety of conditions, including:

• Asthma. A condition in which airway passages become blocked or obstructed causing shortness of breath. Bronchodilators open the airways by relaxing the smooth muscles in these airways. They are among the most commonly used medications for asthma.
  

  

• Chronic bronchitis. Inflammation of the bronchial tube linings that lead to a persistent cough. Short-acting bronchodilators relieve coughing and shortness of breath.
  
  

  

• Chronic obstructive pulmonary disease (COPD). A progressive lung disease that decreases the ability of the lungs to perform ventilation. Bronchodilators smooth muscle constriction in the airways, increasing the flow of air.
  
  

• Mucus in the lungs. A build-up of mucus in the lungs causes a constriction of breathing passages and can lead to coughing. Bronchodilators work to diminish and thin mucus production.
  
  

• Emphysema. A condition in which the normal exchange of oxygen and carbon dioxide in the lungs is impaired due to damaged or collapsed air sacs. Bronchodilators improve air flow.
  
  
• Exercise-induced asthma (EIA). A temporary narrowing of the airways caused by excessive exercise that produces asthma-like symptoms. Bronchodilators administered before and after exercise keep the bronchial air passages open and prevent symptoms associated with this condition.
  
  
• Wheezing. A whistling sound caused by the friction of air going through narrowed airways. Bronchodilators widen the narrow passageways and relax the small tubes in the lungs, making breathing easier.