RadiologyInfo.org

How much radiation is too much?

The question: "How much medical radiation is too much?" has no definitive answer.

The amount of medical radiation that meets your health needs is all that is required.

  • Low need – an x-ray of a broken ankle
    X-ray of a broken ankle

  • Moderate need – a CT scan for adult appendicitis
    Patient in CT scanner with technologist

  • High need – multiple CT scans after a traumatic accident
    CT scan after a traumatic accident

A better question is: How much radiation exposure is required to take care of my condition?

  • There is no fixed answer.
  • It depends on your medical condition.
  • Ask your healthcare provider and radiologist about the benefits of your exam and amount of radiation exposure involved.

Ask your physician two questions:

  1. What do we expect to learn from this x-ray examination?
  2. Will decisions about my healthcare be determined from my imaging exam?

You and your healthcare provider must work together to decide what is necessary and best for you.

One follow-up question to ask might be: Is an x-ray, CT scan or nuclear imaging exam the best exam, or would other exams like ultrasound, magnetic resonance imagine or lab tests, work as well?

Your physician may say:

  1. An ultrasound examination will not be sensitive for what we are trying to see.
  2. An MRI exam takes longer and is not the best test at this time. We might need that later.
  3. A CT exam is very sensitive for the condition you might have, and we have to find out if our diagnosis is correct.
Patient in CT scanner

If the results of an examination will not determine your future course of medical care, then it is unnecessary.

Sometimes, an additional x-ray, CT scan or nuclear imaging exam may help determine treatment or recovery progress. If so, the examination is necessary.

There is no set answer to the question: "How much medical radiation is too much?" Physicians should prescribe what is necessary, avoid overuse and safely use imaging procedures for your healthcare.

The answer depends on your medical need. Asking questions can help you understand why you need an examination and which one is best for your healthcare.

This page was reviewed on August 19, 2011

Sponsored by

Please note

RadiologyInfo.org is not a medical facility. Please contact your physician with specific medical questions or for a referral to a radiologist or other physician. To locate a medical imaging or radiation oncology provider in your community, you can search the ACR-accredited facilities database.

This website does not provide cost information. The costs for specific medical imaging tests, treatments and procedures may vary by geographic region. Discuss the fees associated with your prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a better understanding of the possible charges you will incur.

Web page review process: This Web page is reviewed regularly by a physician with expertise in the medical area presented and is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of North America (RSNA), comprising physicians with expertise in several radiologic areas.

Outside links: For the convenience of our users, RadiologyInfo.org provides links to relevant websites. RadiologyInfo.org, ACR and RSNA are not responsible for the content contained on the web pages found at these links.