BACKGROUND Patients with gastroesophageal reflux disease (GERD) are treated with proton pump inhibitors (PPIs). Those that do not achieve symptom relief, or non-responders, usually undergo esophageal pH monitoring off PPIs in order to confirm the presence of GERD. AIMS To assess the efficacy of the reverse-PPI trial in evaluating the presence of GERD or its recurrence rates, as well as to identify a correlation between the symptom recurrence rates and GERD severity determined by 48-hour Bravo® esophageal pH-monitor testing. METHODS A final total of 205 patients that underwent the 48-hour Bravo® esophageal pH-monitoring study were retrospectively included. Patients discontinued PPI usage for at least 7 days prior to testing, and completed symptom questionnaires during the 2-day test. The Bravo® test was considered positive if the percentage of time with esophageal pH <4 was >4.4%. RESULTS A total of 363 patients underwent 48-hour Bravo® testing and of those patients, 205 were eligible for the study. Ninety-two patients reported symptoms as being «same/better» and 113 as being «worse» after stopping PPIs. Of the 92 patients with improved symptoms, 44 (48%) had documented acid reflux during the Bravo® study, compared with 65 of 113 (58%) patients with worsening symptoms that also complained of acid reflux. Of the 109 patients found to have confirmed GERD upon pH monitoring, 65 (59.6%) reported a worsening of symptoms, compared with 48 of 96 (50.0%) patients without GERD (p=0.043). Main symptoms stated to be worse included heartburn, chest pain, regurgitation, nausea, and belching (p<0.05). Of the 205 patients, 103 were off PPIs for 7 days. Seventy-two of them (68.9%) reported a worsening of symptoms, compared with 40 of the 102 (41.2%) patients that were off PPIs for>7 days (p=0.042) CONCLUSION: Symptom exacerbation following PPI cessation for at least 7 days correlated with acid reflux severity assessed by Bravo® testing. Patients off PPIs for 7 days had a higher likelihood of experiencing worsening symptoms, compared with those off PPIs for more than 7 days. These findings suggest that when PPIs are held for 7 days or less prior to Bravo® testing, acute worsening of upper GI symptoms due to the abrupt discontinuation of therapy may influence the Bravo® results. The etiology of this may be related to rebound acid hypersecretion and needs to be further elucidated in future studies.