Asthma Medicines

As explained in How Asthma Works, asthma involves three main problems in the airways: swelling, increased mucus, and muscle constriction. Bronchodilators are medicines that reduce the muscle constriction component. They relax the muscles in the airways, stopping them from squeezing the passages closed. (Remember: bronchodilators do not reduce inflammation, the central problem in asthma, and for most asthmatics are not enough to keep asthma under control.)

Quick-Acting Bronchodilators are inhaled medications intended to be used as rescue (or "quick reliever") medicines in asthma. If a person is having asthma symptoms (wheezing, coughing, shortness of breath), a couple of puffs of a quick-acting bronchodilator will usually help relieve the symptoms for a few hours. (If asthma symptoms stay the same or get worse despite use of quick-acting bronchodilators, seek emergency care! See Dealing with Asthma Emergencies. Quick-acting bronchodilators can also be used to "pre-medicate" before exercise, to help minimize asthma symptoms during activity. Common quick-acting bronchodilators include albuterol, Proventil, and Ventolin. These medicines can be taken inhaler (also sometimes called an "MDI", a "pump" or a "puffer") or by nebulizer. Taking a quick-acting bronchodilator with a nebulizer is often called a "breathing treatment." See Correct Use of Inhalers and Nebulizers.

Quick-acting bronchodilators usually start to work within 5 or 10 minutes, and their effects usually last 3-4 hours.

Side-effects of quick-acting bronchodilators can include shakiness, nervousness, and a fast heartbeat.

Long-Acting Bronchodilators are similar in their action to quick-acting bronchodilators, but they don't take effect right away, so they can not be used as rescue medicines. They work to keep airway muscles relaxed for longer periods of time. Serevent (generic name: salmeterol), a common long-acting bronchodilator, is an inhaled medicine that takes about 20 minutes to take effect, and then lasts for about 12 hours. It is considered a controller medicine, because although it does not work against inflammation, if taken regularly, it can help manage asthma long-term. See the Theophylline page for information on another, older long-acting bronchodilator.