Rabeprazole is a proton pump inhibitor used to reduce the production of stomach acid. It works by blocking the enzyme responsible for acid secretion in the stomach lining. This decrease in acid helps to relieve symptoms associated with gastroesophageal reflux disease (GERD), peptic ulcers, and other acid-related conditions. Lowering the acid levels not only alleviates discomfort like heartburn and regurgitation but also promotes the healing of the esophagus and stomach lining.