Contrast agent

What is a contrast agent?

A contrast agent is an injectable or ingestible drug that enhances the visualization of anatomical structures (e.g., an organ) or pathological structures (e.g., a tumor).

The contrast agent renders these structures distinct from the surrounding tissues.

There are several categories of contrast agents: iodinated contrast agents for X-ray imaging, gadoline contrast agents for magnetic resonance imaging (MRI), and barium contrast agents for digestive system examinations.

How to prepare for it?

During the injection of a contrast product, the patient must be well hydrated.

The radiologist must be informed if the patient is taking any medication or anti-diabetic treatment, if the patient has undergone a contrast product examination in the last 48 hours, and if the patient has previously experienced allergic reaction.

In case of risk factors concerning the renal function, blood results should be provided.

What happens after the procedure?

The contrast material is eliminated by the kidneys within a few hours.

Risks and inconveniences

Tolerance is generally excellent but some rare undesitableeffects may occur:

With iodized products: feeling of overheating, nausea, or allergy;

With gadoline products: allergy;

With barite products: no contraindication...

Allergy to iodinated contrast agents is not related to a possible allergy to seafood (oysters, mussels, etc.) or to iodine-based skin disinfectants.


The injection of contrast agents in a pregnant woman is not recommended but can be performed at the discretion of the physician.

The pediatrician must be notified after the birth of the child.

A breastfeeding woman must stop breastfeeding for 48 hours if an iodinated contrast agent is being used.

The return home

It is crucial to stay well hydrated during the 48 hours following the examination. This means that 1.5L per day should be consumed.


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