Beta 2 agonists are bronchodilators. They relax smooth muscles around the bronchial tubes allowing air to move more freely. There are many of these preparations available and all work in a similar fashion. These are the medications of choice to treat and control asthma symptoms and are often taken in conjunction with other medications, particularly inhaled corticosteroids.
They are available as short-acting medications as well as more long-acting ones. In general, these medications are well tolerated and are very effective.
| Brand Name | Generic Name |
|---|---|
| Alupent | Metaproterenol |
| Brethine | Terbutaline |
| Bronkosol | Isoetharine |
| Maxair | Pirbuterol acetate |
| Proventil MDI | Albuterol |
| Proventil HFA | Albuterol |
| Serevent (long acting) | Salmeterol xinafoate |
| Tornalate | Bitolterol mesylate |
| Ventolin | Albuterol |
| Volmax | Albuterol |
| Combivent | Albuterol and Atrovent |
Drug Action
Beta 2 agonists relax bronchial smooth muscles but also stimulate the heart muscle as well as skeletal muscles.
Side Effects
Beta 2 agonists are well-tolerated by most people and the side effects decrease with time. The inhaled form is the most effective and causes the least side effects. The most common side effects are:
- Fast heartbeat
- Tremors, nervousness
- Difficulty sleeping
Available Forms
The preferred form of administration of Beta Agonist is by inhalation. Tablets and elixirs are available. The inhaled Beta Agonist may be given by nebulization, metered dose inhalers, or inhaled powered forms. Careful understanding of the correct techniques of inhalation is very important.
The short-acting medications begin to work in minutes and last 4 to 6 hours. The longer acting medication (Salmeterol) does not have a rapid onset of action. Salmeterol (Serevent) will last up to 12 hours but should not be used for acute bronchospasm or wheezing. Salmeterol has not been approved for patients under the age of 12. Both long and short-acting Beta Agonist can be used to prevent exercised induced asthma. Specific use of these medications should be directed by the physician and careful guidelines and understanding of the use of these medications are important.