Who does this impact?
This impacts children ages birth through 3 years old who have received intravenous (IV) contrast that contains iodine for medical imaging.
What is contrast and how is it used?
Contrast with iodine is used to make medical imaging more clear and detailed. It can be used computed tomography (CT) scans or special cardiac tests (catheterizations). It can help your child's care team find possible problems.
What is the new recommendation?
The U.S. Food and Drug Administration (FDA) recommends an extra blood test for children birth through 3 years old after they get intravenous (IV) contrast with iodine. This is to check to see how the thyroid is working. This blood test should be done 2 to 3 weeks after receiving IV contrast.
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What should parents and caregivers do?
Parents and caregivers should talk to your child's health care professional for more information on testing thyroid function or if there are questions or concerns about your child receiving IV contrast.
What is my child’s risk?
All medicines have side effects, but when used correctly, the benefits outweigh these risks. It is important to know that people respond to medicines in different ways. Your care team cannot say how likely it is that your child will have thyroid problems after receiving IV contrast.
What blood testing needs to be done?
The Pediatric Endocrine Society (specialists in thyroid function) recommends a blood test called a Thyroid Stimulating Hormone (TSH) to check thyroid function between 2 and 3 weeks after the contrast is given. In most people, low thyroid function – also called hypothyroidism – is temporary if the iodine exposure does not continue. If this happens, medicine may be given to supplement the low thyroid hormone levels.