Drugs that are metabolized by cytochrome P-450 system such as cyclosporine, disulfiram, benzodiazepines have been reported to show interactions with Omeprazole. Omeprazole can delay the elimination of
diazepam, phenytoin and warfarin. Reduction of warfarin or phenytoin dose
may be necessary when Omeprazole is added to treatment. There is no
evidence of an interaction with theophylline, propranolol or antacids.