title: Plasma level and broncholytic effect of choline theophyllinate after a single dose of a press-coated tablet formulation.
abstract: The broncholytic effect and plasma concentrations of theophylline in 10 asthmatic patients were studied for 8 hours after a single dose of 600 mg choline theophyllinate in press-coated 200 mg tablets. Therapeutic concentrations of theophylline were rapidly achieved and the plasma peak averaged 10.4 mug/ml after 2 hours. The broncholytic effect was closely related to the plasma level of theophylline. The largest change was in FEV1, which was significantly increased 1 to 6 hours after the dose. No patient complained of adverse effects. A theophylline concentration of 7 mug/ml plasma was adequate for a broncholytic effect, but a higher level was required for a maximal response. The results provide a basis for further studies to establish a dosage schedule suitable for prolonged therapy.
mesh_terms: D000328:Adult; D001249:Asthma / Q000503:physiopathology; D001980:Bronchi / Q000187:drug effects*; D002794:Choline / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D013607:Tablets; D013806:Theophylline / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology; D014797:Vital Capacity / Q000187:drug effects
chemical_list: D013607:Tablets; D013806:Theophylline; D007545:Isoproterenol; D002794:Choline