Gastroesophageal Reflux Disease occurs when the lower esophageal sphincter (LES), a muscular valve at the lower end of the esophagus, relaxes inappropriately or weakens. This allows stomach acid and occasionally bile to flow back (reflux) into the esophagus, irritating its lining. Over time, this repetitive exposure to stomach acid can lead to inflammation (esophagitis), erosions, […]