Branica S, Vrabec B, Francetić I, Bakran I
Lijec Vjesn. 1989 Sep-Oct;111(9-10):341-3.
The authors have examined the compliance of asthmatic patients receiving slow-release aminophylline and the relationship between the serum theophylline concentrations and lung function. The effect of meals on the serum concentrations of theophylline was also studied. Twenty-nine patients were analyzed. When the serum drug concentration was measured in a blood sample obtained without prior announcement, 79% of patients were found to have the concentration of theophylline lower than the therapeutic one. When the concentration was measured in a blood sample obtained announced, 55% of patients had therapeutic concentrations. A statistically significant difference (P less than 0.01) in the concentrations of theophylline between the blood samples obtained unannounced and announced was found. There was no correlation between the concentrations of theophylline and PEFR neither in the blood sample obtained unannounced (r = -0.11) nor in that obtained announced (r = 0.09). The theophylline concentrations were higher when the drug was ingested before the meal (means 1 = 70 mumol/L), whereas they were lower when it was ingested after the meal (means 1 = 40 mumol/L). Thus, in hypodosed patients who ingest medicine after the meal, the serum theophylline concentrations might be elevated by taking therapy before the meal.