Prevention of adverse reactions to intravascular contrast media

The exact mechanisms of adverse reactions to contrast media are still imperfectly known; they may, however, be idiosyncratic or non-idiosyncratic. Non-idiosyncratic reactions can be prevented by using new non-ionic contrast agents. Idiosyncratic reactions can be prevented by specific premedication. Patients with a history of idiosyncratic reactions may benefit from prophylactic administration of corticosteroids and antihistamines. Patients who seem more likely than others to react to contrast media must be premedicated, the risk of a reaction being detected and evaluated by questioning. It has recently been suggested that all patients about to receive an intravascular injection of contrast medium should also be premedicated.