A class of anti-asthmatic drug that is used to relieve the symptoms of an asthma attack in-progress and can be used to prevent one from happening in the immediate future. Short term and long term drugs are available and their effect on the lungs vary by their approach to opening up the airways. The most common bronchodilators on the market today, available by prescription, are listed below by generic name with the brand name in parenthesis as well as how they work:

Albuterol (Proventil or Ventolin) are beta2-agonists, which work immediately in opening up the lungs. When Albuterol is inhaled or injected, it will take up to 5 minutes to start working but will only last around 20 to 60 minutes. If ingested in liquid or tablet form, however, it will take as long as 30 minutes to start working, but will last up to 6 hours. The side effects of beta2-agonists can include shaking, rapid and irregular heartbeat, disorientation, nervousness, and paranoia. Most people who use beta2-agonists tend to use them around 3 to 4 times a day to maintain their asthma.

Salmeterol xinafoate (Serevent) is also a beta2-agonist that works significantly longer than Albuterol, in that will last 12 hours per dose. However, this drug takes 20 minutes when inhaled to work, so it is not to be used to stop an acute asthma attack. Recently GlaxoSmithKline has introduced another brand of Salmeterol, this time combining it with corticosteroids. The combination has previously have been quite successful with preventing asthma attacks and treating the problem in the long term. This new drug is called (Advair).

Ipratropium bromide (Atrovent) is a different type of bronchodilator. This one is classified as an anticholinergic, is chemically related to atropine, and is not used as often as beta2-agonists are. It will start working 30 minutes after being used and will last around 2 hours. Its side effects include much the same as beta2-agonists, but can lead to increased bronchospasms and anaphylactic shock.

Theophylline (Quibron) is useful for preventing nighttime asthma attacks, but in recent years has gained disfavor since its side effects have been publicized as being more dangerous than other bronchodilators. Overdoses of Theophylline have resulted in seizures, brain damage and death in some cases.

Bronchodilators are medications used to prevent or reverse bronchospasm, i.e. a constriction of the bronchi. The bronchi are the parts of the airway that branch off from the windpipe into the lungs. They consist of cartilaginous rings and smooth (involuntary) muscle. In people who have asthma, respiratory allergies or COPD (chronic obstructive pulmonary disease), irritation of the bronchi can trigger bronchospasm. The smooth muscle surrounding the bronchi constricts, narrowing the diameter of the bronchi and reducing the volume of air which can pass through. Needless to say, this is very unpleasant and absolutely terrifying. Prompt application of bronchodilators can either prevent or at least alleviate the problem.

Bronchodilators

Brand/Generic Drug Names

Proventil/albuterol, Aminophyllin/aminophylline, atropine sulfate, Ephed II/ephedrine, Primatene Mist/epinephrine, Atrovent/ipratropium, Isuprel/isoprotenerol, Brethine/terbutaline, Theo-Dur/theophylline
Common uses
bronchial asthma, bronchospasm associated with bronchitis, emphysema or other obstructive pulmonary disease, Cheyne-Stokes respiration, prevention of exercise-induced asthma
Pharmacology
Anticholinergics: inhibit acetylcholine interaction with receptors on bronchial smooth muscle
alpha/beta-adrenergic agonists: relax bronchial smooth muscle, increase diameter of nasal passages
beta-adrenergic agonists: act on beta2-receptors relaxing bronchial smooth muscle
Phosphodiesterase inhibitors: increase cAMP relaxing respiratory smooth muscle
Class contraindications
hypersensitivity, narrow-angle glaucoma, tachydysrhythmias, severe cardiac disease
Class precautions
breastfeeding, pregnancy, hyperthyroidism, hypertension, prostatic hypertrophy, seizure disorders
Interactions
varies by drug
Adverse Reactions
tremors, anxiety, nausea, vomiting, throat irritation, bronchospasm, dyspnea
Additional Information
Assess respiratory function
Evaluate therapeutic response: absence of dyspnea, wheezing
Date of most recent Update
August 26, 2002
Further information is available in the writeup for the specific name(s) of this medication class

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