Aims: To study the potential drug interaction between cimetidine and caffeine in a group of children who received cimetidine for gastritis.
Methods: The caffeine breath test was carried out prior to the administration of cimetidine and after 2-3 weeks therapy. The children (n = 1) received 300-800 mg cimetidine daily (11-36 mg kg(-1) day(-1)).
Results: There was no significant change in the 2 h cumulative labelled CO2 following the administration of cimetidine (mean values 5.61% before and 4.87% during cimetidine; Student's t-test P > 0.2).
Conclusions: Cimetidine did not have an inhibitory effect on the metabolism of caffeine in this group of children studied.