ISSN:
1432-1041
Keywords:
theophylline
;
erythromycin
;
drug interaction
;
aminophylline
;
pharmacokinetics
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Summary We have studied the interaction of erythromycin with theophylline. We gave ten healthy volunteers theophylline as an intravenous loading dose (5 mg·kg−1) over 1 h, followed by a maintenance infusion (0.5 mg·kg−1·h−1) for 5 h. A second infusion of theophylline was given after 9 days of treatment with 1 g erythromycin base daily, and the concentrations of theophylline were determined during the infusion periods. The concentrations of erythromycin were measured for 8 h, after one week of treatment, and also after the last erythromycin dose, simultaneously with the second theophylline infusion. Concentrations within the therapeutic range were obtained with both drugs. A significant increase in both AUC and mean plasma concentrations of theophylline was seen during erythromycin treatment. The plasma clearance of theophylline was reduced in 9 of the 10 subjects. Renal clearance increased correspondingly, but the change was not statistically significant. Serum concentrations of erythromycin fell significantly, by more than 30%, with concurrent theophylline medication. We conclude that an interaction between theophylline and erythromycin, affecting both drugs, can be shown with concentrations of the drugs within the therapeutic range.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00637676
