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Published on: July 4, 2014
Temporal variations in trough serum theophylline concentrations at steady state
Journal of Pharmaceutical Sciences
|March 1, 1980
Summary
Morning theophylline levels were higher than afternoon or evening levels in healthy volunteers. These temporal variations in serum theophylline concentrations may impact therapeutic drug monitoring.
Area of Science:
- Pharmacokinetics
- Clinical Pharmacology
Background:
- Theophylline is a widely used medication for respiratory diseases.
- Understanding the pharmacokinetic profile of theophylline is crucial for effective therapeutic drug monitoring.
Purpose of the Study:
- To investigate the temporal variations in serum theophylline concentrations in healthy volunteers receiving multiple doses.
- To determine if the time of day influences steady-state theophylline levels.
Main Methods:
- 14 healthy volunteers received multiple oral doses of theophylline (aminophylline solution or controlled-release capsule).
- Serum theophylline concentrations were measured at various time points (morning, afternoon, evening) to assess trough levels at steady state.
Main Results:
- Significantly higher trough serum theophylline concentrations were observed in the morning compared to the afternoon or evening (p < 0.05).
- Mean morning trough levels for the solution were 11.1 +/- 0.9 mcg/ml (7 am) vs. 9.6 +/- 0.8 mcg/ml (1 pm).
- Mean morning trough levels for the capsule were 13.8 +/- 0.9 mcg/ml (8 am) vs. 10.7 +/- 0.9 mcg/ml (8 pm).
Conclusions:
- Temporal variations in serum theophylline concentrations exist and are influenced by the time of day.
- These findings highlight the importance of considering the time of sample collection for accurate therapeutic drug monitoring of theophylline.
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