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Radiation Protection

Should I take Potassium Iodide (KI) during a radiological emergency?

Never take potassium iodide (KI) or give it to others unless you have been specifically advised to do so by the health department, emergency management officials or your doctor.

KI is issued only in situations where radioactive iodine has been released into the environment, and it protects only the thyroid gland. KI works by filling a person’s thyroid gland with stable iodine so that harmful radioactive iodine from the release is not absorbed, reducing the risk of thyroid cancer in the future.

You should take KI only if you have been specifically advised to do so by local public health officials, emergency management officials or your doctor. It is not an “anti-radiation” drug.

For more information about protecting yourself and your family in the event of a radiological emergency, visit Radiological Emergency Response.

For more information about potassium iodide, visit Frequently Asked Questions about Potassium Iodide at

Return to Frequent Questions about Radiation Protection.