Immediate danger to life: call 999 or 112.

UK Ready is an independent information site. Current official instructions for your area take priority over this general guidance.

Stable iodine, radiation exposure and medical help

Sources checked 13 October 2026

Action summary

1. Stable iodine can protect the thyroid against radioactive iodine when taken at the correct time and dose for the relevant incident.
2. Take stable iodine only when UK authorities or the responsible clinical service instruct you to, using the product and directions they specify.
3. Avoid unsafe substitutes: Iodised salt, iodine supplements and antiseptic iodine are not substitutes for the tablets provided for emergency thyroid protection.
4. If you may have been exposed, follow official instructions about where and when to be assessed.

Stable iodine can protect the thyroid against radioactive iodine when taken at the correct time and dose for the relevant incident. It does not protect the whole body, block external radiation, or protect against other radioactive materials.

Take stable iodine only when UK authorities or the responsible clinical service instruct you to, using the product and directions they specify. Timing and individual health considerations matter. Do not take it merely because an international news story mentions radiation, and do not improvise a dose from online instructions.

Avoid unsafe substitutes: Iodised salt, iodine supplements and antiseptic iodine are not substitutes for the tablets provided for emergency thyroid protection. Do not swallow disinfectants, take high-dose vitamins or rely on an unverified 'radiation detox'. These do not replace sheltering, monitoring and medical care.

If you may have been exposed, follow official instructions about where and when to be assessed. Note where you were, when you were there, whether you were indoors or outdoors, and any cleaning you carried out. This helps responders; it is not a way to calculate your dose at home.

Medical priorities

• Call 999 for life-threatening injury or illness. Tell the operator about possible contamination so responders can plan appropriately.
• Do not postpone urgent lifesaving care because of a fear of contamination. Keep yourself and anyone assisting safe from the continuing hazard.
• Continue essential prescribed medicines according to your care plan. Seek local NHS advice about supply or access difficulties.
• Do not diagnose radiation sickness from nausea alone or assume feeling well excludes exposure. Symptoms overlap with many other conditions.

UK Ready should explain the distinction between radiation exposure and radioactive contamination in simple language. Exposure is receiving radiation; contamination is radioactive material being on or in something. Decontamination removes material where possible. It does not reverse a past dose.

For parents and carers: Do not calculate child doses, pregnancy advice or medication timing through a household calculator. Follow the official incident instructions and medical advice for the person concerned.

Sources

• UK Health Security Agency: What to do in a radiation emergency
• US Centers for Disease Control and Prevention: Nuclear Blasts Frequently Asked Questions
• US Centers for Disease Control and Prevention: Food Drinking Water and Medicine Safety in a Radiation Emergency

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