What is acid reflux?

Acid reflux is when acid comes up from the stomach into the esophagus and causes heartburn or indigestion.

Heartburn, or acid reflux, is acidic stomach fluid regurgitating into the esophagus.

Acid reflux involves a faulty valve in the digestive system. It occurs when a valve called the lower esophageal sphincter releases at the wrong time, sending stomach acids back into the esophagus. This creates a burning feeling in the throat or the chest. Most cases can be relieved with a prescription or an over-the-counter treatment; see a doctor to avoid permanent damage to the esophageal lining.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)
Acid reflux means that acid in the stomach for digesting food backs up through the valve that separates the esophagus from the stomach. This animation shows how acid reflux occurs.

Dr. Bryan Vartabedian, MD
Pediatric Gastroenterologist

Acid reflux, or Gastroesophageal reflux (GER), describes the physiologic condition in which stomach contents come up from the stomach into the esophagus where it doesn't belong.  It's important to understand that this definition says nothing about being sick or miserable. That's because reflux is a physiologic process, which means that it's normal. All of us experience reflux at various times in the day but most of us are unaware when it occurs.

But sometimes the flow of stomach contents into the esophagus can create problems. Gastric contents can irritate the esophagus and upper airway creating symptoms of cough, throat clearing, hoarseness, wheezing and difficulty swallowing. When reflux creates problems we refer to it as gastroesophageal reflux disease (GERD), or pathologic reflux.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.