Heartburn is an uncomfortable feeling or burning pain behind the
breastbone. It may occur after eating, soon after lying down, when bending
forward, or after taking certain medicines.
Heartburn occurs when stomach acid backs up (refluxes) into the
tube that leads from the mouth to the stomach (esophagus), causing pain or
discomfort behind the breastbone, in the center of the chest, and occasionally
in the back of the throat. Sometimes there may be a sour or bitter taste in the
mouth.
Antacids or other nonprescription medicines (such as acid
reducers or acid blockers) may relieve heartburn.
Heartburn can be a symptom of gastroesophageal reflux disease
(GERD).