Taking potassium iodide tablets

What are potassium iodide tablets and why do they need to be taken in the event of a nuclear emergency?

Taking potassium iodide tablets in the event of a nuclear emergency is a particularly effective measure for protecting the thyroid in general, and that of children and teenagers in particular. Excessive exposure to radioactive iodine without absorbing stable iodine can cause cancer of the thyroid.

Iodine tablets are also known as potassium iodide tablets, or stable iodine tablets. Absorption of stable iodine, stable iodine prophylaxis and blocking the thyroid using stable iodine are all synonymous with taking iodine tablets in the event of a nuclear emergency.


How do potassium iodide tablets work?

An accident at a nuclear power station may cause radioactive iodine to be released. Radioactive iodine could then enter the human body, for example through the airways or in food.

In this case, iodine will accumulate mainly in the thyroid gland, an organ that is very sensitive to iodine in general.

The non-radioactive iodine contained within the stable iodine tablets will saturate the thyroid gland and stop radioactive iodine (iodine-131 or other radioactive iodine isotopes) accumulating in the thyroid.

What are iodine tablets made of?

Iodine tablets contain 65 mg of potassium iodide. They can be broken into four.

Iodine tablets also contain: 176 mg anhydrous lactose, microcrystalline cellulose and magnesium stearate.


Do potassium iodide tablets provide effective protection?

Yes. Taking stable potassium iodide tablets 6 hours before radioactive iodine might be inhaled, therefore 6 hours before the radioactive cloud passes over, guarantees 100% protection for the thyroid. If they are taken within 6 hours of possible exposure to a radioactive source, the protection provided is greater than 50%. However, this protection decreases if the iodine tablets are taken more than 12 hours after exposure, and it becomes ineffective after 24 hours.

Iodine tablets only protect the thyroid: therefore they do not protect against contamination from any radioactive components other than radioactive iodine that could be released during an accident at a nuclear power station.

Nor do they protect against X-rays.

Iodine tablets are therefore not an effective method of protecting against all types of irradiation or contamination. It is important to note that the thyroid of a child or young adult is more sensitive than that of an adult. The risk of thyroid illnesses associated with contamination by radioactive iodine (iodine-131 or another radioactive isotope) therefore reduces significantly with age.


Where can potassium iodide tablets be obtained?

In order to ensure that iodine tablets are as widely available as possible, the competent authorities in Luxembourg have established a multi-layered distribution system.

This way the population is guaranteed to obtain iodine tablets in sufficient quantities. In the event of a nuclear accident, households are requested to follow the advice of the authorities organising the distribution of iodine tablets closely.

Will potassium iodide tablets be distributed as a preventative measure?

Yes. The plan makes the provision for potassium iodide tablets to be distributed to all the country's residents as a preventative measure. Each resident receives a personalised letter containing information on this distribution enabling them to obtain one box of potassium iodide tablets from the commune in which they live, or from the pharmacy of their choice.

The first preventive distribution campaign of potassium iodide tablets took place in October 2014.


Will more tablets be distributed at a local level in the event of a nuclear accident?

In the event of a nuclear accident, local distribution points will be set up where people who do not have any potassium iodide tablets (including people who lost their tablets or forgot to obtain any tablets during prior distribution, in the event that they have been destroyed, etc.) can go to obtain them.

In such a situation, the distribution points will be listed in the 'distribution points' section of this website and they will be accessible immediately.

Are the tablets being distributed to maternity wards?

One of the specific provisions that was adopted on the recommendation of the WHO in 1999 was the programme of distribution of stable iodine tablets to maternity wards, with the aim of ensuring that children are protected from exposure to radioactive iodine in the event of a nuclear accident.

The parents of newborns receive a box of potassium iodide tablets and an instruction leaflet upon the birth of their child.

Are schools equipped with a stock of tablets?

Most schools in the country already have a stock of potassium iodide tablets, as do other childcare services (crèches, daycare centres, etc.).

Do pharmacies stock potassium iodide tablets?

The plan makes the provision for potassium iodide tablets to be distributed to all the country's residents as a preventative measure. Therefore, in October 2014 every resident received a personal letter containing information on this distribution and enabling them to obtain a box of potassium iodide tablets either from their commune or from the pharmacy of their choice.

How should potassium iodide tablets be stored?

Like all medication, these tablets should be stored

  • out of the reach of children;
  • in a place that can be accessed easily and quickly;
  • in a clean place away from light, humidity and heat (for example in a medicine cabinet).


What should you do if you don't have any tablets or you have lost them?

If you don't have any or have lost your tablets, please get in touch with your municipal administration.


There is no expiry date on the box of potassium iodide tablets. Is this normal?

Potassium iodide tablets are made from salt and potassium iodide which, when kept in normal storage conditions, do not expire. This is why there is only a manufacture date on the box.

The iodine tablets distributed in Luxembourg in the event of a nuclear accident are regularly checked for effectiveness by the Medicine Division of the National Health Laboratory. If you notice damage to the tablets, for example if they crumble which would make taking them more difficult, they should be replaced.


Are the tablets provided to the different establishments (schools, hospitals, etc.) replaced regularly?

The tablets are replaced when necessary, for example if the box or blister packaging is damaged by water or fire.

The iodine tablets distributed in Luxembourg in the event of a nuclear accident are regularly checked for effectiveness by the Medicine Division of the National Health Laboratory (Division des médicaments du laboratoire national de la santé).


What instructions should be followed before taking potassium iodide tablets?

Potassium iodide tablets must only be taken upon the instruction of the competent authorities.

Carefully read the leaflet enclosed with the box of tablets. It provides information on dosage, which differs for infants, children and adults.

It is not recommended that people over the age of 45 take these tablets as they have no proven beneficial effect for this age category.

How should potassium iodide tablets be taken?

Potassium iodide tablets can be chewed, swallowed whole or dissolved in a drink (milk, fruit juice, sugar water, etc.). Iodine tablets should not be taken on an empty stomach. Having a snack with the tablet can increase one's tolerance and mitigate the taste of iodide.

If dissolved in a drink, they should first be broken into small pieces in a small amount of lukewarm water in a large glass. The tablets may not dissolve easily.

Only fizzy and alcoholic drinks should not be used for dissolving iodine tablets.


How can the tablets be given to a baby?

To administer iodine to a baby, the indicated dose should be dissolved in a small amount of lukewarm water, then added to a liquid (milk, juice, water) in a bottle and shaken well.

The liquid should be drunk straight away as the solution does not keep.

What is the recommended dosage for the tablets? What dose should be taken?

The instructions included with the tablets will help you determine the correct dose to give to each family member. The dose to be given to adults, children, newborns, pregnant women and nursing mothers differs.

Even in the event of a major nuclear accident, it is highly probable that the recommended dose will only need to be taken once.

Newborns, pregnant women and nursing mothers should have no more than one dose.

The following are the current recommended doses (dosage) and should be followed strictly:


Is it dangerous for some people to take potassium iodide tablets?

Any child or adult suffering from the following illnesses or allergies is strongly discouraged from taking iodine tablets:

  • Hypersensitivity to iodine (a rare form of allergy that should not be confused with the more common allergy to the contrast products used for X-rays); 
  • Dermatitis herpetiformis (also known as Duhring's disease):
  • a chronic skin condition characterised by the formation of blisters that resemble those of herpes, a rash and severe itching;
  • Hypersensitivity or allergic vasculitis: an allergic inflammation of the vessels;
  • Congenital myotonia (a genetic muscular illness);
  • Pemphigus vulgaris (a cutaneous illness).

If in doubt you should contact your doctor.

People with thyroid dysfunction, asthma, heart failure, renal impairment or auto-immune illnesses should also consult their doctor before taking iodine tablets.


Should adults over the age of 45 take the tablets in the event of a nuclear accident?

The World Health Organisation (WHO) advises adults over the age of 45 against taking iodine tablets, given that their risk of developing cancer caused by radioactive iodine is much lower than that of children, and that they are particularly sensitive to the side effects of thyroid blocking.

There is no immediate danger however if someone over the age of 45 accidentally takes an iodine tablet.

Can pregnant women and nursing mothers take iodine tablets?

  • Pregnant women

The foetus starts to accumulate iodine in the thyroid at 12 weeks of gestation.

If a pregnant woman takes iodine tablets in the event of a nuclear accident, she also protects her baby at the same time.

Pregnant women and nursing mothers may take the same number of tablets (2 tablets in accordance with current recommended dosage) as other adults and anyone over the age of 12.

  • Nursing mothers

The recommended dose of iodine tablets should be given to newborns and infants.

Iodine tablets (taken by the mother) may not necessarily have the desired thyroid blocking effect for the infant.

During lactation, stable iodine absorbed by the mother is expressed in the mother's milk in variable quantities.

It is not possible to say with any certainty that the quantity of iodine that the infants thus receive is sufficient to protect their thyroid against the effects of radioactive iodine.

If you have a thyroid illness and already take iodine tablets, should you still take potassium iodide tablets?

Yes. The potassium iodide tablets used for iodine prophylaxis in the event of a nuclear accident should not be confused with the iodine tablets that doctors prescribe for thyroid illnesses. The quantity of iodine in the tablets prescribed by doctors is much lower than that of the iodine tablets for use for iodine prophylaxis.

Inversely, potassium iodide tablets for iodine prophylaxis cannot be used to replace the iodine tablets prescribed by the doctor as the levels of iodine they contain are much too high.

If in doubt you should contact your doctor.

Can persons who have had their thyroid removed take potassium iodide tablets?

For anyone who has had their thyroid completely removed, iodide tablets are of no use.

It is nevertheless advisable to check with the doctor to find out whether the whole thyroid gland has indeed been removed.

In the event of only partial removal, iodine tablets have some use and therefore should be taken in the event of a nuclear accident.


If you are lactose intolerant can you take potassium iodide tablets?

There are no known cases of lactose intolerance triggered by taking 65 mg potassium iodide tablets. An intolerance reaction is unlikely as the lactose content is very low (80 mg/tablet). People who do not have to restrict their diets severely in everyday life should have no problems with the lactose content in these tablets.

People who are very intolerant can take lactase preparations to aid digestion. Small quantities of lactose can then be tolerated without experiencing problems.


Can potassium iodide tablets be given to a pet?

Quarter or half a tablet can be given to a pet (dog or cat), depending on their size.

For more information you should consult a vet.


What should be done if a child accidentally ingests the tablets?

If a child swallows several tablets, it is crucial to do the same as with any other medicine and consult a doctor: this is a medical emergency as taking too high a dose of iodine can be poisonous.

However, you should remain calm and do not panic: Stable iodine tablets are not very toxic and ingesting several tablets does not pose an immediate danger to a child.

If a child ingests several tablets they can experience thyroid problems.

The same is true if an adult accidentally takes them.


What are the side effects associated with taking potassium iodide tablets?

Everyone reacts differently to medication. As a result, the side effects of a medicine are not the same for every 'patient'.

That said, iodine tablets can have the following side effects: A metallic taste in the mouth, nausea and vomiting, stomach ache, diarrhoea, skin rashes, agitation and heart palpitations.

In some rare cases, taking potassium iodine tablets can lead to an over-active thyroid, characterised by a high pulse, sweating, insomnia, trembling, diarrhoea or significant weight loss.

In 1986, following the nuclear accident in Chernobyl, 18 million doses of iodine were distributed in Poland. Serious side effects were only observed in three cases.

What should you do if you feel ill after taking potassium iodide tablets?

The side effects associated with taking iodine tablets are mostly mild and go away after a period of time, as long as no more iodine tablets are taken!

If the problem persists or the symptoms worsen, contact your doctor immediately or call 112.

How can new arrivals to the country obtain iodide tablets?

Potassium iodide tablets will be provided to new arrivals to Luxembourg when they register upon arrival in the commune where they will be living.


If you cannot find the answer to your question, do not hesitate to contact us.


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