Gastrozole (Omeprazole) 20mg is a medication that belongs to a class of drugs known as proton pump inhibitors (PPIs). It works by reducing the amount of acid produced in the stomach. Omeprazole works by inhibiting the proton pump in the stomach, which is responsible for the final step in the production of gastric acid. By blocking this enzyme, Omeprazole reduces the amount of acid in the stomach, which helps prevent damage to the esophagus and stomach lining caused by excessive acid.