Pharmacokinetics and safety of montelukast oral granules in children 1 to 3 months of age with bronchiolitis

The single-dose pharmacokinetics of montelukast 4-mg oral granules and tolerability of daily administration of 2 different doses of montelukast (4 mg and 8 mg given once daily for 7 days) versus placebo were evaluated in 12 infants 1 to 3 months of age with bronchiolitis or a history of bronchiolitis and asthma-like symptoms. The population area under the concentration-time curve estimate after a single 4-mg dose of montelukost was 13 195.7 +/- 2309.8 (standard error) ng.hr/mL, 3.6 times higher than historical values in infants 3 to 24 months of age. Six patients had 10 total clinical adverse experiences; none was considered serious or drug related. Three patients had transient drug-related increases in aspartate aminotransferase (montelukast 8 mg [n = 2]; placebo [n = 1]). Despite increased systemic exposure after administration of a single dose of montelukast 4-mg oral granules in infants I to 3 months of age compared with that in pediatric patients 3 to 24 months of age, administration of montelukast at 4 and 8 mg once daily for 7 days in 1- to 3-month-old infants was generally well tolerated.