Purpose

The investigators wish to study the effectiveness of Fexofenadine (an over the counter allergy pill) for the treatment of gastroesophageal reflux symptoms in patients who still have symptoms despite being on a proton pump inhibitor. The investigators will do this by giving participants both Fexofenadine (an H1 blocker) for 2 weeks and placebo (sugar pill) for 2 weeks. The participants will not know which drug they are getting at a particular time. This will help the investigators better assess the true effectiveness of Fexofenadine.