The purpose of this report was to evaluate the frequency and type of reactions to intraarterial iodinated contrast medium injection in horses. Ninety-seven received an intraarterial injection of ionic, iodinated contrast medium for computed tomographic assessment of the distal limb. Nine (9.0%) horses developed a reaction attributable to the contrast medium administration. Of those, 4/97 (4.0%) developed a skin response (three with urticaria, one with facial edema) within 20 min. Five (5.0%) developed elevation of heart rate and/or blood pressure immediately upon administration of the contrast medium. No horse developed a severe reaction such as shock, cardiac, or respiratory arrest. No treatment was necessary in any horse.