Gastroesophageal Reflux Disease (GERD) FAQs: Acid reflux (GERD) is caused by lifestyle factors (alcohol, obesity), medication, diet, medical conditions, and eating habits. Symptoms of acid reflux (GERD) include bad breath, hoarseness, chronic cough, bitter taste in the mouth, wheezing, and a feeling of tightness in the throat. Treatment of acid reflux include lifestyle modifications and medication.