Ocid 20 Capsule belongs to the class of drugs known as proton pump inhibitors (PPIs) used to treat gastroesophageal reflux disease (GERD), stomach ulcer, and Zollinger Ellison syndrome (overproduction of acid due to pancreatic tumour). Normally a thick layer of mucous protects the stomach against its own acid secretion. But, in the long run, it gets eroded by excessive stomach acid production, leading to complications like GERD, peptic ulcer, and Zollinger-Ellison syndrome.