Contrast Injections

This page explains contrast injections and what risks are involved.

DOWNLOADABLE PDF: Contrast Injections

What is a contrast injection?

You are scheduled for an imaging test that uses a substance called contrast. Other names for contrast are contrast medium, contrast agent, contrast material, X-ray dye, and gadolinium contrast. For this test, contrast may be injected into a vein in your arm.

Contrast looks white on X-ray, computed tomography (CT), and magnetic resonance (MR) images. This makes it easier to see the part of your body we are studying.

What risks are involved?

Contrast is usually very safe. But, there are small risks from any injection. Risks include:

  • Injury to a nerve, artery, or vein
  • Infection
  • Allergic reaction to the contrast

Sometimes, people start sneezing or get hives from the contrast. One person out of 1,000 has a more serious reaction to contrast.

Our staff are trained to treat these reactions. Very rarely (in 1 out of 170,000 patients), death has occurred after a contrast injection.

Some people are also at risk of kidney injury from the contrast. Mainly, these are people who already have kidney problems. We are very careful about giving contrast to people who are on dialysis.

You have a higher risk for a complication from the contrast if you:

  • Had a moderate or severe allergic reaction to contrast in the past
  • Have severe allergies to foods or drugs
  • Have unstable asthma that currently needs treatment
  • Have severe heart disease
  • Have multiple myeloma, sickle cell disease, or polycythemia
  • Have severe kidney disease, especially if it is caused by diabetes
  • Are on dialysis

If one or more of these is true for you, please tell your technologist or radiologist. We will plan your test to lower the chance of a complication.

How can I learn more?

If you have any questions about contrast injections, please ask your imaging technologist or radiologist.