OBJECTIVES: Esomeprazole is the first proton pump inhibitor (PPI) to show higher healing rates and faster sustained relief when compared to omeprazole and lansoprazole. Esomeprazole 20mg has been shown to be effective in the long-term treatment of patients with gastroesophageal reflux disease (GORD). However there are no published studies that assess the use of esomeprazole in routine clinical practice in a UK primary care setting. METHODS: A retrospective audit of practice records was performed in a general practice that had made esomeprazole its PPI of choice in early 2001 to determine the clinical and cost implications of the change. RESULTS: The audit identified 180 patients previously on regular PPI therapy who had commenced treatment with esomeprazole. One hundred fifty patients were prescribed low dose esomeprazole (20mg) at the time of their initial therapy change and 146 of these patients were previously on a standard/high dose PPI. After 6 months 137/146 (94%) of these patients remained on esomeprazole 20mg. The majority of patients had no specific diagnosis but had been treated symptomatically. Reassuringly of those patients who did have a specifically recorded diagnosis of reflux oesophagitis or GORD 41/43 (95%) remained on esomeprazole 20mg after 6 months. Prior to the change in therapy to esomeprazole, only 4/180 (2%) of patients were treated with a low dose PPI. Six months after their first prescription for esomeprazole, 142/180 (79%) patients remained on esomeprazole 20mg and a further 5 patients were no longer being treated with any PPI. In addition, savings in PPI costs achieved during the first 6 months after the 146 patients' changed from standard/high dose PPI therapy to esomeprazole 20mg was £7222. CONCLUSION: Changing the therapy of patients on regular standard/high dose PPI to esomeprazole 20mg is a successful strategy; with very few patients switching back to a higher dose.