Information following an injection of X-ray contrast


What is an injection of X-ray contrast media?

This is a colourless solution, which is used to assist in diagnosis in X-ray examinations. During the injection patients often experience a feeling of warmth/flushing this is to be expected and will normally wear off quickly.

After your examination, the X-ray contrast media does not usually cause any problems. Sometimes, however side effects can occur in some people and so it is important that you read the following information after your examination.

Following your examination

If you have attended for your investigation as an outpatient, please remain in the Radiology Department for around 15 minutes after your injection. If you experience pain at or near the injection site during your injection, or immediately following it, please inform a member of staff straight away. 

It is also advisable to remain within the vicinity of the hospital for half an hour following your injection.

Drink plenty of fluids over the next 24 hours.

Watch for any of the following:

  • Wheezing, difficulty in breathing, or tightness or pain in the chest
  • Skin rash, lumps or itchy spots, or other allergic reactions of the skin, such reactions may appear several hours or days after the injection
  • Dizziness or feeling faint 
  • A fever or high temperature 
  • An unexpected change in the amount of urine produced and/or its appearance
  • Swelling or tenderness of your salivary glands or throat
  • Nausea and/or vomiting
  • Abdominal discomfort, pain or diarrhoea

Any of these may be signs of a reaction and need treatment, if you are still within the vicinity of the hospital please return immediately to the Radiology Department.

If you are at home and are concerned about any of the above then please return to the Urgent and Emergency Care Centre (UECC).

Specific information

  • X-ray contrast media does not have any effect on your ability to drive vehicles or use machines.
  • Contrast media contains iodine; this may interfere with tests on the thyroid function. Please tell your doctor if you are to have a thyroid function test in the week following your injection.
  • Please tell your doctor if you are due to have an isotope scan of your thyroid gland within the next two months following the injection of X-ray contrast media.
  • Please also tell your doctor you have received X-ray contrast media if you are due to have blood or urine tests on the same day as the injection.

How to contact us

Clinical Radiology Department

For general enquires about your appointment

01709 424365

For enquiries about preparation for your examination, or to speak to a Radiology Nurse

01709 427086

You may reach an answering machine. Please leave your contact number, and the nurse will phone you back between the hours of 9am to 5pm, Monday to Friday.

Information following an injection of X-ray contrast - patient information leaflet
Produced by Richard Gillott and Adele Roden, May 2021
Revision due May 2023. Version: 1.0. 
©The Rotherham NHS Foundation Trust 2021. All rights reserved.

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