Gastroesophageal reflux disease (GERD) is extremely common in our environment. Its diagnosis is complex. The Lyon Consensus defined, based on 24-hour pH monitoring, that an acid exposure time greater than 6% is definitely abnormal, less than 4% is normal, and between 4 and 6% is a gray area.

The objective of this study is to describe the change in therapeutic behavior based on the result of prolonged pH recording performed with a 96-hour wireless pH measurement capsule in patients with GERD symptoms and an acid exposure time measured by impedanciometry/pH of 24 hours in the gray area. Also, describe the therapeutic outcomes.

Thirty consecutive patients with GERD symptoms and an acid exposure time (AET) measured by impedance measurement/pH between 4 and 6% will be included.

A 96-hour off IBP wireless pH monitoring capsule will be performed. The worst day, the average of the 4 days and the presence of 2 or more days with AET>6% and the 4 days with AET<4% will be recorded.

Patients will be categorized into GERD, reflux hypersensitivity, and functional heartburn. A treatment will be established based on these categories and the GERDq will be measured at 8 weeks of treatment.

Inclusion Criteria:

• Patients ≥ 18 years of age, with symptoms of gastroesophageal reflux, who have undergone a 24-hour impedance pH study without proton pump inhibitors (PPIs), whose AET is between 4 and 6% will be included consecutively. .

Exclusion Criteria:

• Patients with severe comorbidities: Liver cirrhosis, oncological disease, autoimmune diseases, cognitive impairment, psychiatric diseases, bleeding diathesis or anticoagulation
• Pregnant women
• Patients with severe esophagitis, esophageal varices, esophageal strictures, Barrett's esophagus, anti-reflux surgery
• Patients with history of pacemaker or defibrillator, since they can interfere with the signal.
• Patients with nickel allergy
• Patients that refuses to sign the informed consent.

Patients ≥ 18 years of age, with symptoms of Gastroesophageal Reflux, who have undergone a 24-hour impedance pH study without Proton Pump Inhibitors (PPIs), whose AET is between 4 and 6% will be included consecutively. .