Effects of time of dose in relation to food on the bioavailability of Theo-Dur Sprinkle at steady state in asthmatic children.
The effects of administration of Theo-Dur Sprinkle in the fasting state (phase A), 10 minutes before food (phase B), and immediately after food (phase C) were investigated in 12 children with asthma aged 5 to 9 years at steady state. The AUC during the dosing interval was significantly reduced in phases B and C compared with phase A, and bioavailability relative to the fasting state was reduced to 77% +/- 15% (range 61% to 104%) in phase B and 70% +/- 16% (range 40% to 103%) in phase C. The average plasma theophylline concentration during the dosing interval and Cmax were also significantly reduced in phases B and C compared with phase A. The morning predose plasma theophylline concentration in phase B was 22% lower than the predose concentration with Theo-Dur tablets taken 10 minutes before breakfast. The diurnal variation in predose plasma theophylline concentrations was increased from 28% in phase A to 63% in phase C. There was no significant difference in any parameter between administration 10 minutes before food and immediately after food.
Birkett
D J
DJ
Department of Clinical Pharmacology, Flinders University of South Australia, Bedford Park.
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D001249:Asthma / Q000188:drug therapy; D001682:Biological Availability; D002648:Child; D002675:Child, Preschool; D002940:Circadian Rhythm; D003692:Delayed-Action Preparations; D005215:Fasting; D005260:Female; D005502:Food; D006801:Humans; D008297:Male; D011897:Random Allocation; D013806:Theophylline / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D013997:Time Factors
D003692:Delayed-Action Preparations; D013806:Theophylline