['Gastroesophageal reflux is common among patients with postnasal drainage. We investigated whether proton pump inhibitor therapy improved symptoms in patients with postnasal drainage without sinusitis or allergies.', 'In a parallel-group, double-blind, multi-specialty trial, we randomly assigned 75 participants with continued symptoms of chronic postnasal drainage to groups that were given 30 mg of lansoprazole twice daily or placebo. Participants were followed up for 16 weeks. Symptoms were assessed at baseline and after 8 and 16 weeks. Ambulatory pH and impedance monitoring assessed presence of baseline reflux. The primary objective of the study was to determine if acid suppressive therapy improved postnasal drainage symptoms. The secondary objective was to assess if pH and impedance monitoring at baseline predicted response to treatment.', 'Postnasal drainage symptoms improved significantly among patients given lansoprazole compared with placebo. After 8 and 16 weeks, participants given lansoprazole were 3.12-fold (1.28-7.59) and 3.50-fold (1.41-8.67) more likely to respond, respectively, than participants given placebo. After 16 weeks, median (interquartile) percent symptom improvements were 50.0% (10.0%-72.0%) for participants given lansoprazole and 5.0% (0.0%-40.0%) for participants given placebo (P = .006). Neither baseline presence of typical reflux symptoms nor esophageal physiologic parameters predicted response to therapy.'] Does proton pump inhibitor therapy improve symptoms in postnasal drainage?