If the 4-hours serum amylase level was < 3 times the upper normal limit and there was no clinical evidence of acute pancreatitis at that time, patients were allowed free oral fluids and a diet. If the 4- hours serum amylase level was > 3 times the upper normal limit and the patient exhibited pain or nausea and vomiting, then the patient was kept fasting and IV crystalloid fluids with opiate analgesics were prescribed. The following 24 hours blood tests were repeated for serum amylase and the patients were interviewed and examined for clinical evidence of acute pancreatitis.