A new oral formulation of iopamidol, "Gastromiro", was evaluated as a bowel contrast agent during abdominal computed tomography (CT). Comparison was made with the well established agents sodium/meglumine diatrizoate ("Urografin 370") and dilute barium sulphate ("E-Z CAT") in a randomized, blind study of 150 consecutive patients undergoing abdominal and/or pelvic CT. Parameters assessed included quality of bowel opacification, artefact generation, contrast-medium palatibility, side effects and cost. No significant difference was found between the three contrast media in stomach- or small-bowel opacification. E-Z CAT was superior at opacifying the caecum/ascending colon. No compelling reason to choose a particular agent was found in the other assessed parameters, but cost is a significant factor.