60 mg lansoprazole once daily for 5 days is an easy to use method for diagnosing GORD in endoscopy-negative patients. Using 24-h oesophageal pH monitoring as the reference method, the sensitivity was relatively high, while the specificity was lower. Further studies are needed to determine how a PPI could be used as a diagnostic test in GORD.

Patients with longstanding negative-endoscopy reflux disease, whether abnormal or normal 24-hour pH-metry, have symptoms that demand effective therapy. Using PPI on-demand as monotherapy, most patients will need 1 capsule per day.

Rebound acid hypersecretion is probably an infrequent problem in on-demand treatment with PPI in patients with endoscopy-negative reflux disease. A significant increase in p-CgA and s-gastrin was found after 6 months treatment. Fourteen days after withdrawal, CgA and gastrin returned to pretreatment levels. Overall, no aggravation of symptoms was found, but 1/3 experienced increased symptoms.

There is no indication of a rebound aggravation of symptoms 12 to 14 days after a 5-day treatment with lansoprazole 60 mg once daily in patients with reflux symptoms.

Application of a diagnostic PPI test in clinical practice gave a high sensitivity and unusually low specificity compared to placebo-controlled studies, indicating that a test of this nature should be used with caution in everyday practice. Most patients with endoscopy-negative GORD will be diagnosed clinically. A positive test with PPI strengthens the diagnosis but has insufficient specificity to be an objective criterion alone. pH-metry should be unnecessary for the diagnosis of ENGORD in patients with typical reflux symptoms.