Heartburn is a burning sensation that individuals can experience behind their sternum. A common cause of heartburn is gastroesophageal reflux disease (GERD), a condition in which the stomach contents reflux back into the esophagus, and this causes bothersome symptoms or damage to the esophagus. Heartburn due to GERD typically occurs up to 60 minutes after meals and worsens when lying on your back. Individuals with GERD may also complain of regurgitation of sour stomach contents into their mouth. Functional heartburn is burning behind the sternum without evidence of GERD or esophageal motility disorders as the cause. Individuals with functional heartburn do not respond to the usual acid-suppressing treatments for GERD. It is thought that these individuals have increased sensitivity to reflux or even normal amount of acid which may lead to symptoms that other individuals would not experience.
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