Omeprazole (Prilosec) is a proton pump inhibitor (PPI). Over-the-counter (OTC) omeprazole (Prilosec) can ease heartburn, while the prescription version can treat gastroesophageal reflux disease (GERD) and other conditions involving too much stomach acid. Omeprazole (Prilosec) is taken by mouth, typically once daily 30 minutes before breakfast. Some of the more common side effects of omeprazole. Prilosec OTC may also be given together with antibiotics to treat gastric ulcer caused by infection with Helicobacter pylori (H. pylori). Over-the-counter (OTC) Prilosec OTC is used in adults to help control heartburn that occurs 2 or more days per week. Prilosec OTC not for immediate relief of heartburn symptoms. OTC this medicine must be taken on a regular basis for 14 days in a row. PRILOSEC in combination with clarithromycin is indicated for treatment of patients with H. pylori infection and duodenal ulcer disease to eradicate H. pylori in adults. Eradication of H. pylori has been shown to reduce the risk of duodenal ulcer recurrence [see Clinical Studies (14.1) and Dosage and Administration (2)]. Find patient medical information for Omeprazole (Prilosec, Prilosec OTC) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Description 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. Sometimes omeprazole is used in combination with antibiotics (eg, amoxicillin, clarithromycin. Prilosec (omeprazole) is used to treat symptoms of GERD and other conditions caused by excess stomach acid. Includes Prilosec side effects, interactions and indications. 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] It is also used to prevent upper gastrointestinal bleeding in people who are at high risk. [1] Omeprazole is a proton-pump inhibitor (PPI) and its effectiveness is similar to that of. Omeprazole is a medication that reduces the amount of acid in your stomach. It treats heartburn, stomach ulcers and reflux disease. Prilosec OTC is used to treat frequent heartburn. Heartburn occurs when the stomach contents back up and out of the stomach into the esophagus (the tube that connects the throat to the stomach). Most people can safely take omeprazole for a few weeks, depending on why you’re taking it. Learn about long-term use of omeprazole here.