Nexium (Esomeprazole Magnesium) may treat, side effects, dosage, drug interactions, warnings, patient labeling, reviews, and related medications including drug comparison and health resources. Find patient medical information for Esomeprazole (Nexium) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Nexium is a proton pump inhibitor that decreases the amount of acid produced in the stomach. Nexium is used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions involving excessive stomach acid such as Zollinger-Ellison syndrome. Esomeprazole is used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions involving excessive stomach acid such as Zollinger-Ellison syndrome. Esomeprazole is also used to promote healing of erosive esophagitis (damage to your esophagus caused by stomach acid). Esomeprazole, sold under the brand name Nexium (or Neksium) among others, [2] is a medication which reduces stomach acid. [11] It is used to treat gastroesophageal reflux disease, peptic ulcer disease, and Zollinger–Ellison syndrome. [11][12] Its effectiveness is similar to that of other proton pump inhibitors (PPIs). [13] Nexium® capsules are a brand of esomeprazole that treats conditions that cause too much stomach acid like stomach ulcers or reflux disease. It can relieve heartburn.