Learn about the side effects of omeprazole, from common to rare, for consumers and healthcare professionals. Omeprazole Tablets 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. Omeprazole is also used to treat dyspepsia, a condition that causes sour stomach, belching, heart burn, or indigestion. In addition, omeprazole is used to prevent upper gastrointestinal tract bleeding in seriously ill patients. Omeprazole is a proton pump inhibitor (PPI). It works by decreasing the amount of acid produced by the stomach. NHS information about the medicine omeprazole, including what it's used for, who can take it, how to take it and side effects. 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 Prilosec Prilosec OTC Any other medicine known as a proton pump inhibitor Any of the ingredients in the specific product dispensed Your pharmacist can tell you all of the ingredients in. Omeprazole: learn about side effects, dosage, special precautions, and more on MedlinePlus 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. Omeprazole is a proton pump inhibitor that is used to treat symptoms of gastroesophageal reflux disease and other conditions caused by excess stomach acid. Omeprazole is used for a variety of digestive issues, such as acid reflux. Several omeprazole side effects are possible, though dietary changes may help.