Overall, an examination with contrast is a relatively safe examination.
The injection is often, but not always, associated with a warm feeling in the face, neck, and pelvis. This usually lasts for a minute or two and then settles back to normal. Rarely, nausea, chills and sweating may occur, usually at the time of the procedure. These symptoms, by themselves, are not allergic reactions.
Uncommonly, during the injection of the contrast agent, inadvertent extravasation (leak of contrast outside of the vein into surrounding tissues) may occur.
It is important for you to alert radiology staff immediately if you feel pain or discomfort around the needle site during the contrast injection so that the injection can be stopped.
Occasionally (1 in 1000 injections) mild allergic reactions such as rash, hives or sneezing can occur. Again, these usually develop at the time of the procedure. Sometimes these symptoms may occur as a delayed reaction, most often within 30 minutes. They usually do not require treatment and settle rapidly.
Less commonly, more severe reactions can occur including asthma, shock, and circulatory disturbance. Severe life-threatening reactions, up to and including death, have occurred but are very uncommon. The chance of this happening is of the order of 1 in 100,000 injections of contrast agent. The practice has equipment and medications available to begin immediate treatment of serious reactions.
Having an allergy to another drug, food or insect bite causes a very minor, usually insignificant increase in the risk of an allergic reaction to intravenous contrast medium. If you have had intra-venous contrast before without any adverse response, the chance of having a reaction to a subsequent injection is reduced, but not zero.
On the day of your procedure you will be asked to complete a questionnaire which will help us to determine the risk of reaction. Please feel free to talk to our staff regarding any further questions or information you require before proceeding with your examination.
For more information, please see RANZCR Iodinated Contrast Guidelines
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