drug interaction. Hepatic side effects have included elevations in serum transaminases, alkaline phosphatase , bilirubin, and rare cases of hepatitis and hepatic encephalopathy . Fatal fulminant hepatic failure attributed to omeprazole has also been reported. REFERENCE + Product Information. Prilosec (omeprazole). Anonymous Merck & Co, Inc, West Point, PA. PROD; Fulminant hepatic failure