is a chronic condition in which acidic stomach contents leak into the esophagus, causing pain and damaging the esophagus.

Gastroesophageal reflux is a chronic condition in which acidic stomach contents leak into the esophagus, causing pain and damaging the esophagus.

Explanation:

The Esophagus is a part of the digestive tract, which communicates the pharynx with the stomach. Under normal conditions, the gastric or intestinal contents do not pass into the esophagus, since there is a lower esophageal sphincter (IAS) that acts as a valve and prevents the backflow of food. Gastroesophageal reflux (GERD) occurs when stomach contents are returned to the esophagus and causes heartburn (also known as gastric reflux), that is, it occurs when a muscle at the end of the esophagus does not close properly. This allows the stomach contents to return, or reflux, to the esophagus and irritate the mucosa and produce different symptoms and complications.