Effects of some water-soluble contrast media on the colonic mucosa.

Enemas of various solutions were administered to rats to determine if Gastrografin was specifically irritating to the colonic mucosa. Gastrografin was found to cause considerably more inflammation than Hypaque-25, or barium sulfate. Further studies with hypertonic sorbitol, Renografin-76, and Tween 80 suggested that (a) neither hyperosmolality nor the diatrizoate compound itself were damaging to the colon, and (b) Tween 80 most likely plays a major role in Gastrografin's inflammatory effect.