Prevacid belongs to a group of drugs called proton pump inhibitors. It decreases the amount of acid produced in the stomach. Prevacid is used to treat and prevent stomach and intestinal ulcers, erosive esophagitis (damage to the esophagus from stomach acid), and other conditions involving excessive stomach acid such as Zollinger-Ellison syndrome.
Over-the-counter Prevacid OTC is used to treat frequent heartburn that happens 2 or more days per week. Prevacid is not for immediate relief of heartburn symptoms.