The combination of single-dose montelukast and loratadine on exercise-induced bronchospasm in children.

The aim of the study was to evaluate the protective effect of single-dose, combination treatment comprising montelukast (5 mg) and loratadine (10 mg), on exercise-induced bronchoconstriction in asthmatic children. The combination was compared to placebo, loratadine and montelukast alone. Nineteen children were enrolled in a double-blind randomised, single-dose, crossover study. For each treatment patients undertook two treadmill exercise tests, 2 and 12 h respectively after single-dose administration. No significant differences were seen in the maximum fall in forced expiratory volume in one second (FEV1) 2 h after treatment and placebo. Whereas significant differences in maximum fall in FEV1 were observed between treatment groups 12 h after administration. Loratadine alone did not show any significant protection or any additional effect in comparison with montelukast alone. Single doses of montelukast and montelukast plus loratadine were significantly more effective than loratadine at 12 h. The present study, performed using single-dose treatments, demonstrated that maximal protective effect by montelukast was obtained 12 h after dosing and that montelukast plus loratadine did not result in significant additive bronchoprotective effects on exercise-induced bronchoconstriction.