Nexpro-20/Nexpro-40/Nexpro IV Drug Interactions

Nexpro-20/Nexpro-40: Interaction with other medicinal products and other forms of interaction: Effects of Esomeprazole on the Pharmacokinetics of Other Drugs: The decreased intragastric acidity during treatment with esomeprazole might increase or decrease the absorption of drugs if the mechanism of absorption is influenced by gastric acidity. In common with the use of other inhibitors of acid secretion or antacids, the absorption of ketoconazole and itraconazole can decrease during treatment with esomeprazole.
Esomeprazole inhibits CYP2C19, the major Esomeprazole metabolizing enzyme. Concomitant administration of 30mg Esomeprazole resulted in a 45% decrease in clearance of the CYP2C19 substrate diazepam. This interaction is unlikely to be of clinical relevance. Concomitant administration of 40mg Esomeprazole resulted in a 13% increase in trough plasma levels of phenytoin in epileptic patients.
Concomitant administration of 40 mg esomeprazole to warfarin treated patients showed that, despite a slight elevation in the trough plasma concentration of the less potent R-isomer of warfarin, the coagulation times were within the accepted range. However, as with all patients receiving warfarin, monitoring is recommended during concomitant treatment with esomeprazole.
In healthy volunteers it was reported that, concomitant administration of 40mg esomeprazole resulted in a 32% increase in area under the plasma concentration-time curve (AUC) and a 31% prolongation of elimination half-life (t_½) but no significant increase in peak plasma levels of cisapride. This interaction did not alter the influence of cisapride on cardiac electrophysiology.
Esomeprazole has no pharmacokinetic interaction with amoxicillin or quinidine.
Studies evaluating concomitant administration of esomeprazole and either naproxen (non-selective NSAID) or rofecoxib (COX-2-selective NSAID) did not identify any clinically relevant interaction.
Effects of Other Drugs on the Pharmacokinetics of Esomeprazole: Esomeprazole is metabolized by CYP2C19 and CYP3A4. Concomitant administration of esomeprazole and a CYP3A4 inhibitor, clarithromycin (500mg twice a day), resulted in a doubling of the exposure (AUC) to esomeprazole. Dose adjustment of esomeprazole is not required.