Background Elevated intra-abdominal pressure is associated with morbidity in critically ill patients. Enteral feeding is important for these patients but may cause complications. Objective To compare the effects of 2 intermittent feeding schedules on intra-abdominal pressure in patients receiving mechanical ventilation. Methods A single-blinded, prospective, parallel-group, randomized controlled trial was conducted in an intensive care unit in a teaching hospital in Egypt. Fifty adult patients requiring more than 48 hours of mechanical ventilation were enrolled. Patients were randomly sorted into 2 study groups. The intervention group received intermittent enteral feedings 5 times daily at 4-hour intervals. The control group received intermittent enteral feedings 10 times daily at 2-hour intervals. Both groups fasted for 8 hours overnight. Intra-abdominal pressure was measured 7 times: at admission and before and after the first 3 feedings on the third day of the intensive care unit stay. Results One-way repeated-measures analysis of variance showed that mean intra-abdominal pressure was higher in the control group before the first feeding ( t = 2.27, P = .03) but was higher in the intervention group after the second feeding ( t = 2.51, P = .02) and after the third feeding ( t = 2.41, P = .02). Vomiting and diarrhea were not significantly different between the groups. More constipation and abdominal distension occurred in the intervention group than in the control group. Conclusion Intra-abdominal pressure was not significantly affected by feeding interval. However, reducing the time interval between intermittent enteral feedings may minimize the risk for constipation and abdominal distension.