Bitter or acidic taste in the mouth
People who have heartburn often have a somewhat bitter or acidic taste [2] in their mouths. This is because heartburn often cooccurs with or is caused by acid reflux. During acid reflux, some of the acidic contents in the stomach make their way up the esophagus. Sometimes these contents reach the mouth or the back of the throat and taste bitter and acidic. If a sufficient amount of this acid reaches the mouth, you may find it uncomfortable grinding your teeth against each other because of the acridness of the stomach acid.