Hesperidin in orange juice reduces the absorption of celiprolol in rats

It has been reported that the intestinal absorption of celiprolol, an antihypertensive drug, is inhibited when it is taken with orange juice; it has been suggested that element(s) in citrus juice are responsible for this. In the present study, the pharmacokinetic interaction between celiprolol and orange juice was characterized through in vivo experiments with rats. Celiprolol 5 mg/kg was injected into the rat duodenum together with 5 ml/kg of neutralized orange juice or the same concentration of hesperidin as in the orange juice. Plasma celiprolol concentrations were measured by liquid chromatography–electrospray ionization–mass spectrometry (LC‐ESI‐MS). Concomitant administration of orange juice or hesperidin with celiprolol significantly decreased the area under the plasma concentration–time curve (AUC) by 74% and 75%, respectively, compared with control. These findings suggest that hesperidin is responsible for the decreased absorption of celiprolol and that orange juice taken with celiprolol has an inhibiting effect on intestinal absorption of the drug. Copyright © 2008 John Wiley & Sons, Ltd.