The effect of H2-antagonists on the absorption of bupropion in rats.

Bupropion absorption was investigated by oral administration of bupropion alone or in combination with cimetidine or ranitidine to rats. Blood samples were collected before and at 0.25, 0.5, 0.75, 1.0, 1.5, 2.0, 3.0, 4.5 and 6 h after bupropion administration. The assay of bupropion in plasma was carried out by an HPLC method. Cimetidine or ranitidine did not significantly affect the plasma bupropion concentrations on concurrent administration. No significant differences were observed between area under the curves (AUC)s, maximum plasma concentration, time to peak and the half-life of bupropion among the three groups. These results indicate that neither cimetidine nor ranitidine significantly affects the rate or the extent of bupropion absorption in rats.