Absolute and relative bioavailability of a slow release theophylline preparation in asthmatic children.
This study was carried out on 14 asthmatic children aged 7-13 years. They all received three preparations (aminophylline by intravenous infusion, lysine theophyllinate orally in solution and slow release theophylline orally as capsules) in a single dose of 100 mg active ingredient in a crossover design. Plasma theophylline concentrations, determined by a fluorescent polarization immunoassay, were evaluated both by compartmental and non-compartmental analysis. After administration of slow release theophylline, its maximum plasma concentration and the time needed to reach this were (+/- SD) 3.19 +/- 0.63 microgram/ml and 8.71 +/- 2.30 h, respectively, compared to 4.51 +/- 0.94 microgram/ml and 1.96 +/- 0.85 h, respectively, for the oral normal release solution. Mean absolute and relative percentage bioavailabilities for slow release theophylline in asthmatic children were (+/- SD) 92.7 +/- 23.2% and 83.14 +/- 14.69%, respectively. These are similar to the values found with other slow release formulations in paediatric patients.
Boner
A L
AL
Paediatric Clinic, University of Verona, Italy.
De Stefano
G
G
Vallone
G
G
Plebani
M
M
Ventura
P
P
D000293:Adolescent; D001249:Asthma / Q000097:blood* / Q000188:drug therapy; D001682:Biological Availability; D002648:Child; D003692:Delayed-Action Preparations; D005260:Female; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D013806:Theophylline / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use
D003692:Delayed-Action Preparations; D013806:Theophylline