title: Serum theophylline profile with once-daily theophylline (Uniphyl) following conversion from intravenous theophylline in adult asthmatic patients.
abstract: Although guidelines are available for conversion from intravenous (IV) theophylline to twice-daily, oral, controlled-release theophylline, the optimal method for conversion to Uniphyl, a chronotherapeutically formulated, once-daily theophylline preparation, has not been previously evaluated. The present study was designed to prospectively evaluate a method for converting patients from IV theophylline to Uniphyl, to formulate simple, practical dosage recommendations for use in clinical practice. Ten patients with acute exacerbation of asthma receiving IV theophylline for > or = 48 hours and with steady state serum theophylline concentrations (STCs) between 4.5 and 15.5 mg/L (25 and 86 mumol/L) were enrolled into the study. Patients with STCs > or = 4.5 and < 12 mg/L (> or = 25 and < 66 mumol/L) and those with STCs > or = 12 and < or = 15.5 mg/L (> or = 66 and < or = 86 mumol/L) received their first Uniphyl dose immediately following termination of IV theophylline (No Time Lapse [NTL] group) and after a 4-hour delay (Time Lapse [TL] group), respectively. The differences in the area under the curve values between Uniphyl dosing and IV theophylline were 11% in the NTL group (1214.6 +/- 247.9 mumol/h.L-1 vs 1370.4 +/- 148.1 mumol/h.L-1, 95% confidence interval, 74% to 103%; P = 0.068) and 10% in the TL group (1959.4 +/- 165.1 mumol/h.L-1 vs 1784.6 +/- 119.4 mumol/h.L-1, 95% confidence interval, 103% to 117%; P = 0.013).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pharmaceutical Services, Royal Alexandra Hospital, Edmonton, Alberta, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Fradette
authors.forename: M
authors.initials: M
authors.lastname: Babich
authors.forename: E G
authors.initials: EG
authors.lastname: Friesen
authors.forename: J S
authors.initials: JS
authors.lastname: Archibald
authors.forename: N
authors.initials: N
authors.lastname: Babul
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001249:Asthma / Q000188:drug therapy* / Q000378:metabolism; D003692:Delayed-Action Preparations; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D011446:Prospective Studies; D013806:Theophylline / Q000008:administration & dosage* / Q000097:blood* / Q000493:pharmacokinetics
chemical_list: D003692:Delayed-Action Preparations; D013806:Theophylline