no decrease in viral shedding was observed in rhinovirus infected individuals treated with montelukast and there was no significant difference in reported cold symptom scores compared to placebo treated individuals analysis of secondary outcomes suggests that montelukast may protect against reductions in lung function and increases in sputum eosinophils caused by common cold infections during the recovery phase the percentage of sputum eosinophils was elevated in the placebo group while the montelukast group remained at baseline levels further peak expiratory flow was not decreased in the montelukast treated patients other studies have shown that montelukast treatment has no effect on the respiratory symptoms of patients with acute respiratory syncitial virus bronchiolitis see bisgaard h et al study of montelukast for the treatment of respiratory symptoms of post respiratory syncitial virus bronchiolitis in children am j respir crit care med 2008 178 854 860 and proesmans m et al montelukast does not prevent reactive airway disease in young children hospitalized for rsv bronchiolitis acta paediatr 2009 98 1830 34 however some studies indicate that treatment with montelukast reduced the number of days with worsened asthma symptoms and unscheduled doctor 39 s visits in children with mild allergic asthma and resulted in a.