5-Hydroxy Acetate Omeprazole-d3 is the labeled analogue of 5-Hydroxy Acetate Omeprazole (H749990), an intermediate in the synthesis of 5-Hydroxy Omeprazole (H948863), the main metabolite of Omeprazole (O635000), which binds covalently to proton pump. It inhibits gastric secretion. Used as an anttiulcerative.