Results of studies assessing the effectiveness of anti-inflammatory agents for young children with asthma have been inconsistent. This may be because some children in this age group have episodic wheezing that occurs during a viral illness. Only a small number of children have recurrent or chronic wheezing caused by allergic asthma. When assessing the response of asthma to anti-inflammatory agents, it is important to differentiate between viral-induced and allergy-induced wheezing. Measurement of exhaled nitric oxide has proved helpful for this purpose; levels of exhaled nitric oxide are elevated in children with asthma and can be reduced with anti-inflammatory therapy. However, in younger children, poor cooperation often keeps inhaled anti-inflammatory treatments from being deposited in the lungs. One possible alternative to inhaled anti-inflammatory agents is the oral agent montelukast (Singulair). Straub and associates evaluated the effect of montelukast on exhaled nitric oxide levels and lung function in preschoolage children with asthma.

The participants were children two to five years of age who recently had been diagnosed with asthma and had a family history of asthma in one or both parents, exhaled nitric oxide levels consistent with asthma, and a positive allergy test. Before the study, researchers measured exhaled nitric oxide levels (after any anti-inflammatory agents had been stopped) and lung functions, including responsiveness to bronchodilator therapy. Participants took 4 mg of montelukast daily for four weeks. At the end of the intervention, the lung function studies and exhaled nitric oxide tests were repeated. Pill count and parental reporting were used to measure compliance with the regimen.

Thirty children were included in the study. The mean exhaled nitric oxide levels declined significantly (33.1 to 11.6 parts per billion). The mean airway resistance also improved significantly, but the mean bronchial dilating effect did not change significantly during the course of the study.

The authors conclude that use of montelukast in preschool-age children with allergic asthma has a positive impact on lung function and air inflammation. They add that montelukast may be a good alternative to other first-line anti-inflammatory agents in preschoolage children with allergic asthma. They state that this would be particularly true in those who are unable to cooperate fully with inhaled therapy.