Lack of a pharmacokinetic interaction between lansoprazole or pantoprazoleand theophylline

Aim: To study the potential pharmacokinetic interaction between lansoprazol e or pantoprazole and theophylline at steady state. Methods: Theophylline 200 mg extended-release formulation was administered twice daily on days 1-11 to 30 healthy, non-smoking males. On days 5-11, 15 subjects received concomitant lansoprazole 30 mg once daily (o.d.) and 15 subjects received concomitant pantoprazole 40 mg o.d. Results: No significant changes in the steady-state theophylline maximum pl asma concentration (C-max), time to C-max (T-max), minimum plasma concentra tion (C-min), area under the plasma concentration-time curve over the 12-h dosing interval (AUC(0-12)), or apparent total oral clearance (CL/F) were o bserved within the two treatment groups when theophylline was administered alone or in combination with lansoprazole or pantoprazole. In addition, no significant differences in the changes of steady-state theophylline pharmac okinetics from day 4 to day 11 were noted between the two treatment groups. Treatment with theophylline in combination with either lansoprazole or pan toprazole was well tolerated. All adverse events were transient and rated m ild to moderate in severity. Conclusion: Co-administration of either lansoprazole or pantoprazole in hea lthy subjects does not significantly affect the steady-state pharmacokineti cs of theophylline at the therapeutic doses tested.