Twenty-eight patients with histologically proven reflux esophagitis were randomly allocated to receive either De-Nol (tripotassium dicitrate bismuthate) or placebo for three weeks. Significant decreases in symptoms frequency and severity were noted in De-Nol group comparing with placebo group (p less than 0.01). Objective improvement in esophageal endoscopic appearance was obtained in 78.5% of the patients treated with De-Nol and only in 14.2% of those receiving placebo. De-Nol appears to be an effective drug in the treatment of reflux esophagitis, but this should be confirmed by further studies.