Asthama is a chronic inflammatory disorder of the airway with recurrent airflow obstruction. Chronic airway inflammation is invariably associated with injury and repair of the bronchial epithelium, which results in structural and functional
changes
known as remodeling Inflammation, remodeling, and altered neural control of the airway are responsible for both recurrent exacerbations of asthma and more permanent airflow obstruction. Asthma exacerbations may be caused by a variety of risk
factors
including allergens, pollutants, foods and drugs. Prevention of exacerbation aims to reduce the exposure to these risk factors to improve the control of asthma and reduce medication needs.
Although no cure for asthma has yet been found, it is resonable to expect that in most patients with asthma, control of the disease can and should be achieved and maintained. Patient education involves a understanding of why and how to manage
asthma and
how to prevent asthma exacerbation.
Medications for asthma can be administered in different ways, including inhaled, oral and parenteral. The major advantage of delivering drugs directly into the airways via inhalation is that high concentrations can be delivered more effectively
to
the
airways, and systemic side effects are avoided or minimized.
Therapy should be selected on the basis of the severity of a patient’s asthma. According to the GINA guideline 2002, for intermittent asthma, no daily medication is reconmmended for the vast majority of patients. A rapid-acting inhaled
β2-agonist
may
be taken as needed to relieve asthma symptoms. The occasional patient with intermittent asthma, but severe exacerbations, should be treated as having moderate persistent asthma. Patients with mild persistent asthma require controller medication
every
day to achieve and maintain control of their asthma. Treatment with an inhaled glucocorticosteroid is preferred. Sustained-relase theophyline cromolynes or a leukotriene modifier are other options. The preferred therapy for moderate persistent
asthma
is regular treatment with a combination of inhaled glucocorticosteroid and a long-acting inhaled glucocorticosteroid and a long-acting inhaled β2-agonist twice daily. Sustained-release theophyline or a leukotriene modifier are alternatives to
the
β2-agonist in this combination therapy. An alternative to combination therapy is a higher dose of inhaled glucocorticosteriod.
The primary therapy for severe persistent asthma includes inhaled steroids at higher doses plus a long acting inhaled β2-agonist twice daily. Any available medications including oral steroid may be added to control asthma symptoms. Once control
of
asthma is achieved and maintained for at least 3 months, a gradual reduction of the maintenance therapy should be tried.
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