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Published on: July 4, 2014
Temporal variations in trough serum theophylline concentrations at steady state
Abstract:
Temporal variations in serum theophylline concentrations were observed in 14 healthy volunteers receiving multiple doses of theophylline. After repeated oral doses (6.9--18.2 mg/kg/day) of theophylline as either a nonalcoholic aminophylline solution or a controlled-release capsule, trough theophylline levels at steady state were significantly higher (p less than 0.05) in the morning than in the afternoon or evening. With the solution, the mean (+/-SE) trough serum level at 7 am was 11.1 +/- 0.9 micrograms/ml, and at 1 pm it was 9.6 +/- 0.8 micrograms/ml. With the capsule, the mean (+/-SE) trough serum level at 8 am was 13.8 +/- 0.9 micrograms/ml, and at 8 pm it was 10.7 +/- 0.9 micrograms/ml. Temporal variations in serum theophylline concentrations have not been reported previously and may be important in therapeutic monitoring.
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