Thyroid protection in nuclear accident

When radioactive iodine-131 is released (Chernobyl 1986, Fukushima 2011) the thyroid concentrates the isotope and receives a high local radiation dose, raising cancer risk. A single high dose of stable potassium iodide (130 mg in adults, 65 mg in children) saturates the thyroid and blocks radioactive iodine uptake. WHO and SEEN recommend dosing only after an official advisory in the first hours of the event; without such an advisory self-administration is unjustified and risky.

1 drug

Also known as: Stable iodine prophylaxis in radiation emergencies, Thyroid blockade with stable iodine, Potassium iodide after Chernobyl / Fukushima

Drugs used for this condition

AIodine (umbrella: potassium iodide, kelp / Fucus vesiculosus)First line · Trace element; substrate of thyroid hormone synthesisThyroid blockade with stable potassium iodide during a radiation emergency releasing iodine-131. WHO and FDA approve the regimen: 130 mg for adults, 65 mg for children 3–18 years, 32 mg for 1 month – 3 years, 16 mg for neonates. The drug is taken on official Civil Protection advisory in the first hours after the release. AEMPS warns: self-administration of potassium iodide outside a radiation event is unjustified and risky – thyrotoxicosis, hypothyroidism and arrhythmia risk. Iosat / ThyroShield / Iodomarin 130 mg are prescription-only for emergency stockpiling; in Spain the stockpile is held by municipal Civil Protection.

How to read tiers A–F

Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit