Ranitidine 150 mg is used to treat conditions such as gastroesophageal reflux disease (GERD), ulcers in the stomach or intestines, and conditions where the stomach produces too much acid (such as Zollinger-Ellison syndrome). It belongs to a class of medications called H2 blockers, which work by reducing the production of stomach acid. Ranitidine helps relieve symptoms such as heartburn, acid indigestion, and stomach discomfort caused by excess acid. It can also be used to prevent ulcers from recurring and to treat acid-related damage to the esophagus. However, it's important to use ranitidine under medical supervision and according to prescribed guidelines.