Gastroesophageal reflux disease (GERD)

Gastroesophageal reflux disease (GERD), or just acid reflux, is when stomach acid frequently flows back into the esophagus. Heartburn is the most common symptom of GERD.

Gas

Gas is when air builds up in your small intestine and large intestine. Flatulence is when gas passes through the rectum and belching, or burping, is when gas passes through the mouth.