Heartburn is a common symptom of acid reflux characterized by a burning sensation in the chest or throat. It occurs when stomach acid flows back up into the esophagus, the tube that carries food from the mouth to the stomach. This reflux of stomach acid is caused by a malfunctioning of the lower esophageal sphincter (LES), a muscular valve that separates the stomach from the esophagus. When the LES doesn’t close properly, stomach acid can flow back up into the esophagus, causing irritation and discomfort.
In addition to a burning sensation in the chest or throat, other symptoms of heartburn may include a sour taste in the mouth, difficulty swallowing, and a feeling of food stuck in the throat.
