Rabeprazole Ketoconazole

Rabeprazole (AcipHex) [Antiulcer Agent/Proton Pump Inhibitor] Uses PUD, GERD, ZE H. pylori Action Proton pump inhibitor Dose 20 mg/d may T to 60 mg/d H. pylori 20 mg PO bid X 7 d (w/ amoxicillin and clarithromycin) do not crush/chew tabs Caution [B, /—] Disp Tabs SE HA, fatigue, GI upset Interactions t Effects OF cyclosporine, digoxin -1- effects OF ketoconazole EMS None OD May cause N, tach, dry mouth, and drowsiness symptomatic and supportive... 

The bioavailability of ketoconazole is reduced by both omeprazole and rabeprazole. Other proton pump inhibitors are expected to behave similarly. Omeprazole also markedly reduces the absorption of itraconazole capsules, but not the oral solution. Proton pump inhibitors are predicted to reduce the bioavailability of posaconazole. The bioavailabilities of fluconazole and voriconazole are not significantly affected by omeprazole. Esomeprazole levels may also be Increased by voriconazole.Omeprazole levels are Increased by ketoconazole, and markedly increased by fluconazole and voriconazole. 

In a randomised placebo-controlled study 18 healthy subjects were given ketoconazole 400 mg before and after taking rabeprazole 20 mg daily or a placebo for 7 days. Significant decreases in the ketoconazole AUC and maximum serum levels were found, representing about a 30% reduction in its bioavailability. There was no evidence that ketoconazole affected rabeprazole metabolism. 

The interaction between ketoconazole and rabeprazole is also established, but the reduction in the bioavailability is only moderate (30%) and it may be possible to accommodate this by raising tiie antifungal dosage. 

Humphries TJ, Nardi RV, Spera AC, Lazar JD, Laurent AL, Spanyers SA. Coadministration of rabeprazole sodium (E3810) and ketoconazole results in a predictable interaction with ketoconazole. Gastroenterology (1996) 110 (Suppl), A138. 

A group of nine specific pharmaceuticals from aqueous environmental samples (flubendazole, propiconazole, pipamperone, cinnarizine, ketoconazole, miconazole, rabeprazole, itraconazole and domperidone) was also analyzed with LC-ESI/MS/MS by Van De Steene et al. ... 

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