Background: The efficacy of H2-receptor antagonists in functional dyspepsia is equivocal and the therapeutic place of proton pump inhibitors in functional dyspepsia is unknown.
Aim: To evaluate the efficacy of proton pump inhibitor therapy in functional dyspepsia.
Methods: Patients (n = 1262) with a clinical diagnosis of functional dyspepsia (persistent or recurrent epigastric pain or discomfort for at least 1 month and a normal upper gastrointestinal endoscopy) were randomized to receive omeprazole 20 mg, 10 mg or identical placebo, for 4 weeks. Symptoms were assessed using validated measures. Helicobacter pylori status was determined pre-entry by a 13C-urea breath test.
Results: On an intention-to-treat analysis (n=1248), complete symptom relief was observed in 38% on omeprazole 20 mg, compared with 36% on omeprazole 10 mg and 28% on placebo (P = 0.002 and 0.02, respectively). Among those with ulcer-like and reflux-like dyspepsia, complete symptom relief was achieved in 40% and 54% on omeprazole 20 mg, and 35% and 45% on omeprazole 10 mg, respectively, compared with 27% and 23% on placebo (all P < 0.05, except omeprazole 10 mg in ulcer-like dyspepsia, P = 0.08). There was no significant benefit of omeprazole over placebo in dysmotility-like dyspepsia. Symptom relief was similar in H. pylori-positive and negative cases.
Conclusions: Omeprazole is modestly superior to placebo in functional dyspepsia at standard (20 mg) and low doses (10 mg) but not in patients with dysmotility-like dyspepsia.