Abstract
Leukotriene receptor antagonist is now one of the choice as a controller medicine for childhood bronchial asthma. We assessed the inhibitory effects of a single dose of pranlukast hydrate on exercise-induced bronchoconstriction (EIB). Subjects were 9 children who showed a postexercise fall of FEV1 of at least 30%. Exercise challenges were performed with or without oral administration of pranlukast hydrate (3.5mg/kg) 5hr in advance. The mean maximal % fall in FEV1 and PEF without medication were 45.1±14.0% and 48.7±14.6% respectively, which were reduced significantly to 23.9±20.1% and 22.7±22.1% respectively with the administration of pranlukast hydrate. The degree of inhibitory effect of pranlukast hydrate was various in each subject, being remarkable (>60%) in 5 subjects, whereas being ineffective (<5%) in 2. The former showed a tendency to lower serum eosinophil cationic protein (ECP). The study demonstrated the potency of pranlukast hydrate administered before the exercise to attenuate EIB in childhood asthma.
