what is losec
(Redirected from Losec). Omeprazole (INN) /oÊËmÉprÉzoÊl/ is a proton pump inhibitor used in the treatment of dyspepsia, peptic ulcer disease, gastroesophageal reflux disease, laryngopharyngeal reflux, and ZollingerâEllison syndrome.eptic ulcers are sores that develop in the lining of either the stomach or the duodenum due to damage from stomach acid. The most common cause of a peptic ulcer is infection by Helicobacter pylori.