Omeprazole is used to treat certain conditions where there is too much acid in the stomach. It is used to treat gastric and duodenal ulcers, erosive esophagitis, and gastroesophageal reflux disease (GERD). GERD is a condition where the acid in the stomach washes back up into the esophagus. Omeprazole is a medication that treats conditions that cause too much stomach acid like heartburn, stomach ulcers and reflux disease. It works by reducing the amount of acid in your stomach. It can take several days before your stomach pain gets better after taking this medication. What is this medication? Omeprazole is a proton pump inhibitor (PPI) that works by blocking the acid pump in your stomach, reducing how much acid it makes and giving irritated or damaged tissue a chance to heal. Omeprazole brand names are Prilosec, Prilosec OTC, and generic brands are available. Overview: Omeprazole is used for heartburn, acid reflux, and other conditions where you have too much acid in your stomach. It works by reducing how much acid your stomach makes and usually takes. Prilosec (Omeprazole) may treat, side effects, dosage, drug interactions, warnings, patient labeling, reviews, and related medications including drug comparison and health resources. Prilosec is a proton pump inhibitor that decreases the amount of acid produced in the stomach. Prilosec is used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions caused by excess stomach acid. Find lasting relief from frequent heartburn with Prilosec OTC. One daily pill blocks heartburn so you can enjoy meals and restful nights. Learn about omeprazole (Prilosec) usage and dosing. Read the latest news and reviews about the drug as well as potential side effects and popular alternatives. PRILOSEC is indicated for short-term treatment of active duodenal ulcer in adults. Most patients heal within four weeks. Some patients may require an additional four weeks of therapy. Omeprazole, sold under the brand names Prilosec and Losec among others, is a medication used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome. [1].