Asthma Treatment

Definition

Treatment of asthma can be divided into long-term control and quick-relief medications.

Description

Long-term control medications are taken daily to maintain control of persistent asthma. They primarily serve to control airway inflammation.

The quick-relief medications are taken to achieve prompt reversal of an acute asthma “attack” by relaxing bronchial smooth muscle.

Many asthma medications can be administered orally or by inhalation. Metered-dose inhalers (MDI’s) are the most widely used method, but dry powder inhalers are becoming popular. Nebulizer therapy is reserved for patients who are unable to use MDI’s because of difficulties with coordination.

Long-Term Control Medications

Corticosteroids: Steroids, more correctly called corticosteroids, can change the course of asthma for the better. Corticosteroids are drugs used to treat many disorders. They come in three forms: inhaled, oral and injectable.

Inhaled forms are for everyday management and are generally used daily. Dosages for inhaled corticosteroids vary, depending on the specific medication and delivery device. Inhaled corticosteroids include: Beclovent, Vanceril, Pulmicort Turbuhaler, AeroBid, Flovent, and Azmacort.

Oral tablets or pills (e.g. prednisone) are used to treat more severe asthma. Injectable forms are used to treat asthma in emergencies.

Corticosteroids work so well because they help stop the inflammatory reaction that causes asthma in the first place. Other drugs used for asthma, bronchodilators such as theophylline and beta-agonists, just treat immediate symptoms like coughing and wheezing. Bronchodilators do not change the course of asthma or stop the inflammation that causes it.

Inhaled forms of corticosteroids are used most often to treat asthma. The medication goes directly to where the inflammation is in the lungs. Because very little medication gets into the bloodstream, serious side effects are unusual.

Most inhaled asthma medications for adults are administered with a metered-dose inhaler (MDI), but unlike the bronchodilators, inhaled corticosteroids do not work immediately.

Corticosteroids must also be taken on the schedule your doctor has given you, even if you feel fine. If you have no symptoms, it is probably because you have been taking the medication carefully.

Your doctor may also ask you to continue taking a bronchodilator between corticosteroid doses if you have mild symptoms. You may find that you need your bronchodilator less often when you use corticosteroids.

You may develop a slight cough or throat irritation with corticosteroids. Another possible side effect, but one that is not too likely, is that you may develop a yeast infection in your mouth. This is easily treated, but you can usually prevent it entirely by using a spacer with your inhaler. You may want to use a spacer anyway, because it makes the inhaler easier to use and more effective. Washing your mouth after inhalation may also decrease side effects.

Long-term bronchodilators: Cromolyn sodium and nedocromil are long-term control medications that can be used to prevent asthma symptoms and improve airway function. Salmeterol is indicated only for long-term prevention of symptoms. Theophylline may provide mild bronchodilation in asthmatics.

Leukotriene modifiers: This is the newest class of medications for long-term control of asthma. Zileuton, zafirlukast and montelukast cause modest improvements in lung function and reductions in asthma symptoms.

Desensitization:Immunotherapy for specific allergens may be a consideration in certain asthma patients.

Quick-relief Medications

Beta-adrenergic agents: Short-acting, inhaled bronchodilators are the most effective treatment during asthma exacerbations.

These medications relax airway smooth muscle and allow for easier airflow. These medications include albuterol (Proventil, Ventolin), bitolterol (Tornalate), pirbuterol (Maxair), and terbutaline (Brethaire).

One or two inhalations of a short-acting inhaled beta adrenergic agonist from an MDI are usually adequate for mild to moderate symptoms. Severe exacerbations may require up to four inhalations every few hours. Nebulizer therapy may be more effective for some patients.

Regularly scheduled daily use is not generally recommended. Increased use or lack of effect may indicate a need for stronger long-term control therapy.

Corticosteroids: They are one of the important forms of treatment for patients with severe asthma. These medications may be given via the intravenous route for critically ill patients, for example in the Emergency Room. If you have moderate to severe asthma, your physician may advise you to have oral corticosteroids (e.g. prednisone) available at home for early administration. Delays in administering corticosteroids may result in delayed benefits.

Anticholinergics: They may reverse certain forms of bronchospasm (tight bronchial smooth muscle). Ipratropium is the only available agent.

Phosphodiesterase inhibitors: These include aminophylline. Not generally recommended for asthma exacerbations.

Antibiotics: If you have a bacterial respiratory infection (fever, productive cough) during your asthma exacerbation, antibiotics may be given.

Symptoms

(see Health Profile: Asthma)

Treatment

Asthma cannot be cured, but it can be controlled with proper asthma management.

The first step in asthma management is environmental control. Asthmatics cannot escape the environment, but through some changes, they can control its impact on their health.

Listed below are some ways to change the environment in order to lessen the chance of an asthma attack:

• Clean the house at least once a week and wear a mask while doing it

• Avoid pets with fur or feathers

• Wash the bedding (sheets, pillow cases, mattress pads) weekly in hot water

• Encase the mattress, pillows and box springs in dust-proof covers

• Replace bedding made of down, kapok or foam rubber with synthetic materials

• Consider replacing upholstered furniture with leather or vinyl

• Consider replacing carpeting with hardwood floors or tile

• Use the air conditioner

• Keep the humidity in the house low

The second step is to monitor lung function. Asthmatics use a peak flow meter to gauge their lung function. Lung function decreases before symptoms of an asthma attack - usually about two to three days prior. If the meter indicates the peak flow is down by 20 percent or more from your usual best effort, an asthma attack is on its way.

The third step in managing asthma involves the use of medications. There are two major groups of medications used in controlling asthma - anti-inflammatories (corticosteroids) and bronchodilators.

Anti-inflammatories reduce the number of inflammatory cells in the airways and prevent blood vessels from leaking fluid into the airway tissues. By reducing inflammation, they reduce the spontaneous spasm of the airway muscle. Anti-inflammatories are used as a preventive measure to lessen the risk of acute asthma attacks. The corticosteroids are given in two ways - inhaled via a metered dose inhaler (MDI) or orally via pill/tablet or liquid form. The inhaled corticosteroids are flunisolide (AeroBid), triamcinolone (Azmacort) and beclomethasone (Beclovent and Vaceril). The oral corticosteroids (pill/tablet form) are prednisone (Deltasone, Meticorten or Paracort), methylprednisolone (Medrol) and prednisolone (Delta Cortef and Sterane). The oral corticosteroids (liquid form) are Pedipred and Prelone. These liquid forms are used for asthmatic children.

The Food and Drug Administration (FDA) approved two drugs: zafirlukast (Accolate) and zileuton (Zyflo), a new class of anti-inflammatories called leukotriene inhibitors. Taken orally, these drugs work by inhibiting leukotrienes (fatty acids that mediate inflammation) from binding to smooth muscle cells lining the airways. These drugs prevent rather than reduce symptoms and are intended for long-term use.

Other inhaled anti-inflammatory drugs include cromolyn sodium (Intal) and nedrocromil (Tilade).

Bronchodilators work by increasing the diameter of the air passages and easing the flow of gases to and from the lungs. They come in two basic forms - short-acting and long-acting. The short-acting bronchodilators are metaproterenol (Alupent, Metaprel), ephedrine, terbutaline (Brethaire) and albuterol (Proventil, Ventolin). These drugs are inhaled and are used to relieve symptoms during acute asthma attacks. The long-acting bronchodilators are salmeterol (Serevent), metaproterenol (Alupent), and theophylline (Aerolate, Bronkodyl, Slo-phyllin, and Theo-Dur to name a few). Serevent and Alupent are inhaled and theophylline is taken orally. These drugs are sometimes used to control symptoms in special circumstances, such as during sleep or when intensive exposure to a particular irritant can be predicted (i.e. pollen season). Atrophine sulfate (Atrovent) is another highly effective bronchodilator. This drug opens the airways by blocking reflexes through nerves that control the bronchial muscles.

Some people cannot control the symptoms by avoiding the triggers or using medication. For these people, immunotherapy (allergy shots) may help. Immunotherapy involves the injection of allergen extracts to "desensitize" the person. The treatment begins with injections of a solution of allergen given one to five times a week, with the strength gradually increasing.

Note: Asthmatics vary considerably in their responses to different types, combinations and amounts of medicines so therapy must be carefully tailored to the individual. Even medication that may work well with some asthmatics may not be effective for others. Please discuss your individual situation with your doctor and both of you will determine a course of management that is best for you.

Prevention

Periodic assessments and ongoing monitoring of asthma are essential to determine if therapy is adequate. Patients need to understand how to use a peak flow meter and understand the symptoms and signs of an asthma exacerbation.

Regular follow-up visits (at least every six months) are important to maintain asthma control and to reassess medication requirements.

Patients with persistent asthma should be given an annual influenza vaccine.

Questions to Ask Your Doctor

Is there any further testing that can be done?

What further treatment do you recommend?

Will you be prescribing something new? What are the side effects?

What is an MDI (inhaler)? What is a spacer?

Am I using my MDI (inhaler) correctly?

What is a peak flow meter? How do I use it? How often?