Omeprazole is a medication that belongs to a class of drugs known as proton pump inhibitors (PPIs). It works by reducing the amount of acid produced in the stomach, which helps treat conditions like gastroesophageal reflux disease (GERD) and stomach ulcers. By lowering stomach acid, omeprazole can relieve symptoms such as heartburn and discomfort. Typically taken as a pill or capsule, omeprazole is usually prescribed for short-term use, although some people may take it for longer periods under medical supervision. Common side effects can include headache, nausea, and diarrhea. Always consult a healthcare professional before starting or stopping any medication.