title: Intrapatient variability in theophylline kinetics.
abstract: Seven asthmatic children had repeat determinations of theophylline pharmacokinetic measurements over three- to nine-month intervals. Significant intrapatient variability was found in the theophylline clearance and t1/2, which determine the dosage regimen necessary to provide given average, peak, and trough theophylline plasma levels. Repeat clearance values were, on average, 52% different from the original clearances, with a range of -57% to +142%. A single determination of theophylline kinetic measurements in any individual patient cannot be used routinely to predict future theophylline dosage regimens for that patient.
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000097:blood / Q000188:drug therapy; D002648:Child; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D012129:Respiratory Function Tests; D013806:Theophylline / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use
chemical_list: D013806:Theophylline