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? Find patient medical information for Omeprazole (Prilosec, Prilosec OTC) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings 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 (generic name: omeprazole) is a drug used to treat acid reflux, heartburn, GERD (gastroesophageal reflux disease), and gastric ulcers. It functions through reducing the amount of acid your gastric produces. Prilosec (Omeprazole) may treat, side effects, dosage, drug interactions, warnings, patient labeling, reviews, and related medications including drug comparison and health resources. Find lasting relief from frequent heartburn with Prilosec OTC. One daily pill blocks heartburn so you can enjoy meals and restful nights. Prilosec delayed-release oral suspension is a prescription medicine used to reduce the amount of acid in your stomach. Prilosec is a proton pump inhibitor. 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. 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].