title: Lack of effect of dirithromycin on theophylline pharmacokinetics in healthy volunteers.
abstract: Twelve healthy volunteers were enrolled in an open-label, randomized, crossover study. Subjects received single doses of theophylline (5 mg/kg) alone and after a 10 day course of dirithromycin (two 250 mg tablets od). The study phases were separated by a 3 week washout period. Serum samples were collected before and for 24 h after theophylline doses. Serum theophylline concentrations were measured via a validated immunoassay system and the data were modelled via non-compartmental analysis. When the control phase (i.e. no dirithromycin) was compared with the treatment phase (i.e. with dirithromycin), theophylline exposures as measured by AUC0-->infinity were not significantly different: 141.7+/-25.9 and 136.4+/-33.1 mg x h/L respectively (P = 0.16). No significant changes in other theophylline pharmacokinetic parameters were evident. These results indicate that theophylline can be safely co-administered with dirithromycin.
authors.affiliation: Department of Pharmacy Services, Bassett Healthcare, Cooperstown, NY 13326-1394, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: McConnell
authors.forename: A N
authors.initials: AN
authors.lastname: Nafziger
authors.forename: G W
authors.initials: GW
authors.lastname: Amsden
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D019540:Area Under Curve; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D004415:Dyspepsia / Q000139:chemically induced; D004917:Erythromycin / Q000031:analogs & derivatives / Q000494:pharmacology; D005260:Female; D006261:Headache / Q000139:chemically induced; D006801:Humans; D018942:Macrolides; D008297:Male; D008875:Middle Aged; D013806:Theophylline / Q000009:adverse effects / Q000493:pharmacokinetics*; D014202:Tremor / Q000139:chemically induced
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides; C053853:dirithromycin; D004917:Erythromycin; D013806:Theophylline