Acid-suppressive medications are commonly used in hospitalized patients, but, to date, little is known about the overall use of these drugs in the hospital setting. AIM: To evaluate the appropriateness of acid-suppressive therapy in a large teaching hospital in northern Italy, and the fall-out of hospital prescription in general practice. METHODS: The use of antisecretory agents was monitored for 1 month in adult patients consecutively admitted to L. Sacco University Hospital by reviewing their clinical charts. The appropriateness of each prescription was reviewed jointly by two consultant gastroenterologists. RESULTS: A total of 46.8% of 799 hospitalized patients received acid-suppressive therapy. Ranitidine was the most frequently used drug (44.4%), followed by pantoprazole (31.8%) and omeprazole (23.0%). Stress ulcer prophylaxis and the prevention of non-steroidal anti-inflammatory drug-induced ulcer accounted for 60.4% of the indications for use. Overall, 68% of prescriptions were not appropriate as determined by consensus review; 56.4% of patients receiving unnecessary prophylactic treatment whilst in hospital were discharged on therapy, and 46% were still receiving the treatment 3 months later. CONCLUSIONS: Acid-suppressive agents are over-used in hospitalized patients. Most of the inappropriate hospital prescriptions are for ulcer prophylaxis in low-risk patients. This unnecessary use may also induce inappropriate drug consumption in general practice.