Esomeprazole potassium Description A proton pump inhibitor. Used as a antiulcerative agent. Specifications Cas No. 161796-84-5 Product ID E7357 Product Name Esomeprazole potassium Synonym Omeprazole potassium Formula Wt. 383.51 Purity ≥98% Store Temp Ambient Ship Temp Ambient References Garnett WR.An. Pharmacother.30:1425-36(1996).