title: Intersubject variability of serum theophylline concentration after single dose of uncoated controlled release theophylline tablet administration in asthmatic patients.
abstract: Various reports indicate significant intersubject variation in the rate of absorption of controlled release theophylline products that are commercially available. Serum theophylline concentration was estimated in 17 asthma patients treated with controlled release theophylline tablet (mean dose: 5.6 +/- 0.6 mg/kg, mean body wt: 49.82 +/- 9.05 kg). The mean maximal concentration (Cmax) of 5.57 +/- 1.65 micrograms/ml occurred at mean time of maximal concentration (Tmax) of 3.3 +/- 1.36 (mean +/- SD) hours. Mean minimal concentration (Cmin) was 3.164 +/- 1.1 micrograms/ml (mean +/- SD) at mean time of minimal concentration (Tmin) of 5.77 +/- 1.77 (mean +/- SD) hours. The mean percent fluctuation was 112.95 +/- 183.45 (mean +/- SD) but in 4 out of 17 patients, percent fluctuation was 107.29 to 823.10. Therefore, 23.5% patients treated with controlled release theophylline tablet had wide fluctuations in serum theophylline concentration.
authors.affiliation: Department of Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: N S
authors.initials: NS
authors.lastname: Raj
authors.forename: R
authors.initials: R
authors.lastname: Guleria
authors.forename: A
authors.initials: A
authors.lastname: Misra
authors.forename: J N
authors.initials: JN
authors.lastname: Pande
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001249:Asthma / Q000188:drug therapy*; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D013607:Tablets / Q000493:pharmacokinetics / Q000627:therapeutic use; D013806:Theophylline / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D001993:Bronchodilator Agents; D003692:Delayed-Action Preparations; D013607:Tablets; D013806:Theophylline