With the resurgence of oral cholecystography for assessing gallbladder function prior to new treatment methods, it is important to be aware of the possibility of gastro-duodenal retention of contrast medium, and its implications. Six patients who had retained Telepaque in the stomach or duodenum at oral cholecystography are described here. In each patient there was underlying pathology, including gastritis, peptic ulceration and neoplasm. The presence of retained contrast medium in the stomach or duodenum is a useful indication of disease in these areas.