title: Reduction of serum theophylline levels by terbutaline in children with asthma.
abstract: We studied the effect of oral terbutaline on serum theophylline levels in 12 children with asthma. Sustained-release theophylline (10 mg/kg twice a day) was given with placebo or terbutaline (0.075 mg/kg three times a day) in a chronic, randomized, double-blind, crossover design. The trough serum theophylline concentration fell from 13.8 +/- 4.0 to 10.8 +/- 3.6 micrograms/ml and the peak expiratory flow rate increased from 285 +/- 30 to 310 +/- 29 L/min after terbutaline. Further investigation is needed to clarify the mechanism of action by which terbutaline decreases serum theophylline levels.
mesh_terms: D001249:Asthma / Q000188:drug therapy*; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D002851:Chromatography, High Pressure Liquid; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D004341:Drug Evaluation; D004347:Drug Interactions; D006801:Humans; D010366:Peak Expiratory Flow Rate; D011674:Pulse / Q000187:drug effects; D011897:Random Allocation; D013726:Terbutaline / Q000494:pharmacology*; D013806:Theophylline / Q000097:blood / Q000627:therapeutic use*
chemical_list: D003692:Delayed-Action Preparations; D013806:Theophylline; D013726:Terbutaline