The antibacterial effect of varying concentrations of sucralfate was studied on Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus grown in both agitated batch and continuous culture. The minimum inhibitory concentrations estimated with the two methods were in close agreement, ranging from 5 to 15 mg sucralfate/ml, concentrations easily attainable in gastric juice after a standard adult dose. Batch culture results indicated a dose-dependent effect. This study provides further evidence for an antibacterial effect by sucralfate against a range of species associated with respiratory tract infection in ventilated patients.