Wednesday, October 22, 2014

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. Metered-dose inhalers are changing from the type propelled by liquified chlorofluorocarbons (CFCs) to a new, CFC-free delivery system (see the National Heart Lung and Blood Institute review on the new MDIs at http://www.nhlbi.nih.gov/health/public/lung/asthma/mdi.htm). Nebulizer therapy is reserved for patients who are unable to use MDI’s because of difficulties with coordination.

Symptoms

see Asthma report.

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.

Three drugs, zafirlukast (Accolate), montelukast (Singulair) and zileuton (Zyflo), are part of a newer class of anti-inflammatories called leukotriene modifiers. Taken orally, these drugs work by inhibiting leukotrienes (fatty acids that mediate inflammation) from binding to smooth muscle cells lining the airways. They also reduce the recruitment of inflammatory cells to the airways. These drugs both prevent and 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.

Questions

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?

I have heard that some medications are ‘second-line’ treatments. What does that mean?

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.