The effect of fasting on gallbladder opacification during oral cholecystography: a controlled study in normal volunteers.

The effect of fasting on gallbladder opacification during oral cholecystography was studied in 10 normal volunteers using 2 oral cholecystographic agents, iopanoic acid and sodium tryopanoate. Radiographs made 15 hours after ingestion of the contrast agents revealed good opacification of the gallbladder in all subjects when iopanoic acid was administered with a meal and when sodium tyropanoate was administered in the fasting state; in only 2 subjects when iopanoic acid was given in the fasting state; in 3 when given in the fasting state with ox bile; and in 3 when sodium tyropanoate was given with a meal.