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).
In GERD, the valve at the top of the stomach (where the stomach and the esophagus connect) does not close tightly enough. This allows the contents of the stomach to move up into the esophagus.
GERD usually causes a feeling of burning, warmth, heat, or pain that often starts in the upper part of your belly, just below your breastbone (sternum). This feeling (called heartburn) may spread in waves upward into your throat, and you may have a sour taste in your mouth. Heartburn is sometimes called indigestion, acid regurgitation, sour stomach, or pyrosis.