Lack of a pharmacokinetic interaction between lansoprazole or pantoprazole and theophylline

AIM: To study the potential pharmacokinetic interaction between lansoprazole 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 plasma concentration (Cmax), time to Cmax (Tmax), minimum plasma concentration (Cmin), area under the plasma concentration-time curve over the 12-h dosing interval (AUC0-12), or apparent total oral clearance (CL/F) were observed 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 pharmacokinetics from day 4 to day 11 were noted between the two treatment groups. Treatment with theophylline in combination with either lansoprazole or pantoprazole was well tolerated. All adverse events were transient and rated mild to moderate in severity. CONCLUSION: Co-administration of either lansoprazole or pantoprazole in healthy subjects does not significantly affect the steady-state pharmacokinetics of theophylline at the therapeutic doses tested.