Objectives: Although abdominal pain is a cardinal feature of choledocholithiasis, there has been little formal study of the features of pain in this condition. The objective of this study was to prospectively evaluate the clinical, laboratory, and radiological features of common bile duct stones, focusing on the characteristics of abdominal pain.Methods: All of the patients evaluated for choledocholithiasis at the time of endoscopic cholangiopancreatography during a 3.5-year period were prospectively interviewed and evaluated. Specific features of abdominal pain were recorded, including pertinent radiographic and laboratory data and endoscopic cholangiopancreatography findings.Results: During the 42-month study period, 61 patients (mean age 55.3 years; 42.6% men) were identified; 31 patients (50.8%) had undergone cholecystectomy. Of the 52 patients who reported pain, abdominal pain was most commonly described as constant (100%), located in the epigastrium alone (65%) or both the epigastrium and the right upper quadrant (25%), occurring at night (44.3%), and radiating to the back (59.6%) with the number of distinct pain episodes before diagnosis ranging from 1 to 20. The median duration of pain was 3 hours and ranged from 20 minutes to 2 days. Associated symptoms of nausea (69.2%) and vomiting (30.7%) were common. No differences in pain characteristics were detected between those with or without a prior cholecystectomy. Liver tests were abnormal in all patients, with serum transaminase values being most elevated.Conclusions: In our study, choledocholithiasis had a characteristic pattern of constant epigastric pain radiating to the back that was associated with nausea. A prior episode was common. The most common laboratory abnormality was transaminase elevation, and the most common imaging finding was common bile duct dilatation. [ABSTRACT FROM AUTHOR]