NEXIUM Packets is a prescription treatment for acid reflux, also known as gastroesophageal reflux disease or GERD, and related conditions. Proton pump inhibitor drugs benefits and side effects, danger oral capsule is a prescription drug that decreases the amount of acid the stomach makes. It can be used to treat GERD, esophagitis, and other. Learn about the potential side effects of Nexium (esomeprazole). Includes common and rare side effects information for consumers and healthcare professionals. Find a comprehensive guide to possible side effects including common and rare side effects when taking Prilosec (Omeprazole) for healthcare professionals and consumers. Find a comprehensive guide to possible side effects including common and rare side effects when taking Prevacid (Lansoprazole) for healthcare professionals and consumers. Nexium is used to treat GERD and other conditions involving excessive stomach acid. Learn about side effects, interactions and indications. You may report side effects related to AstraZeneca products by clicking here. The information on this Web site should not take the place of talking with your doctor. Learn about possible side effects of NEXIUM and find other Important Safety Information. Left side abdominal pain may arise from the internal organs of the abdomen, namely the gastrointestinal and urinary tract, chest, upper pelvic organ, abdominal wall.