Abstract: Prodrugs of the pyridyl methyl sulfinyl benzimidazole type proton pump inhibitor drugs have a hydrolyzable sulfinyl or arylsulfonyl group attached to the benzimidazole nitrogen, or include a group that forms a Mannich base with the benzimidazole nitrogen. The prodrugs of the invention hydrolyze under physiological conditions to provide the proton pump inhibitors with a half life measurable in hours, and are capable of providing sustained plasma concentrations of the proton pump inhibitor drugs for longer time than presently used drugs. The generation of the proton pump inhibitor drugs from the prodrugs of the invention under physiological conditions allows for more effective treatment of several diseases and conditions caused by gastric acid secretion.