Bronchodilators are medications commonly used by people with asthma. They relax
the muscles that surround the airways and allow the airways (the tubes that carry
air into and out of the lungs) to open up. Some bronchodilators act quickly to stop
asthma symptoms (such as wheezing, coughing, or shortness of breath) that are often
caused by narrowed airways. Known as rescue, quick-relief, or fast-acting medications,
these bronchodilators are meant to be used when a person first notices symptoms, but
their effect doesn't last long. Other bronchodilators, known as controller medications,
are longer acting and are used to control, or prevent, asthma symptoms.