Bronchodilators are medicines that help open the Bronchial Tubes (airways)
of the lungs, allowing more air to flow through them.
People with Asthma have trouble breathing, because their airways are
inflamed and become narrowed. Normally, air moves smoothly from the mouth
and nose through the airways and into the tiny air sacs of the lungs as a
person breathes in. Breathing out (exhaling) happens automatically when the
person stops breathing in.
In a person with Asthma, breathing in (inhaling) is not a problem. Incoming
air can slide around the blockage, because the act of breathing in makes the
airways expand. The problem comes when the person with asthma tries to
breathe out. The air can no longer get past the blockage, and it remains
trapped in the lungs. The person can then only take shallow breaths.
Bronchodilators work by relaxing the smooth muscles that line the airways.
This makes the airways open wider and allows air to leave the lungs. These
drugs also are used to relieve breathing problems associated with Emphysema,
Chronic Bronchitis, and other lung diseases.
Some Bronchodilators are inhaled, using a Nebulizer or an inhalation
Aerosol. Others are taken as injections or by mouth. Most are available only
by prescription, but a few, such as Ephedrine, can be bought without a
physician's prescription. Examples of Bronchodilators are Albuterol
(Proventil, Ventolin), Epinephrine (Primatene), Ipratropium (Atrovent),
Metaproterenol (Alupent, Metaprel), and Terbutaline (Brethine).