MRI - Magnetic Resonance Imaging - CT - Computed Tomography - Xray - Ultrasound - Digital X-rays

Are Contrast Agents Safe?

The vast majority do not experience any reaction but there are a few people who are sensitive, or allergic, to contrast agents.

The use of iodinated compounds may cause untoward effects which are generally of mild or moderate nature, as well as more severe ones, with possible fatal anaphylactoid reactions.

Mild and moderate symptoms include heat and pain (at the site of injection, chest, back), chills, fever, dizziness, fainting, nausea, vomiting, sweating, pallor, shortness of breath, blood pressure changes, and widespread skin rash and swelling.

More severe effects may involve the cardiovascular system, including changes in blood pressure and heart rate and shortness of breath.

The risk of the most severe reaction is between 1 in 25 000. It is impossible to predict who will react to contrast (unless you have had a previous injection and reaction), although some people are at more risk, e.g. severe asthmatics.

This group will be identified at NRL by means of a questionnaire given to all patients whose test may involve a contrast injection.

There is slight but potential reaction between the some contrast agents and diabetes tablets. We will check this prior to your study.