Predicting the Response to Montelukast by Genetic Variation in Asthmatics

Inclusion Criteria:

• Male and female subjects, age 18-55
• Clinical history consistent with asthma
• Mild to moderate asthma as determined by pulmonary function tests--60% or higher of predicted FEV1 for age, sex and race.
• Response to hypertonic saline, which will be the main outcome variable measured.

Exclusion Criteria:

• Smokers (total lifetime smoking history>10 pack-years, any in the past year)
• Pregnant woman-if of childbearing age, not using an acceptable form of birth control.
• Use of a leukotriene modifier within the past month
• Use of inhaled or oral steroids within the past month.
• Emergency room visit for asthma exacerbation within the past 6 weeks.
• Intubation for asthma exacerbation in the past 10 years.
• Adverse reaction to inhaled beta-agonists in the past.
• No recent (past 48 hours) use of anticholinergics, theophylline, antihistamines, pseudoephedrine.
• Patients will also be asked not to use any short acting beta-agonists for 6 hours and long-acting beta-agonists for 48 hours before their initial visit (when pulmonary function evaluation will be performed).
• Lung disease other than asthma
• Significant medical illness other than asthma