What are iodine tablets?
Iodine tablets are pharmacy-only medicines that you should take only after consulting a doctor. Iodine tablets mainly contain the salt potassium iodide in different dosages. A rough distinction is made between:
Low-dose iodine tablets: As a supplement, they compensate for an iodide deficiency in the body (usually around 200 microgram dosage). Such a deficiency can develop if you take in too little iodine through food over a long period of time. Iodine tablets can then prevent the formation of a goiter (struma prophylaxis).
In addition, iodine tablets can cover a temporarily increased iodine requirement, for example during pregnancy – but only as needed and after consulting a doctor.
Never take these high-dose iodine tablets on your own initiative! Read more about this below in the section “Iodine blockade in case of nuclear hazard”.
Side effects in case of overdose
Iodine tablets can irritate the stomach lining – especially if you take them on an empty stomach. An excessive amount of potassium iodide may also cause skin and mucous membrane irritation and stomach pain.
In individual cases, temporary thyroid overactivity (hyperthyroidism) may also occur. Typical complaints are then manifested by:
- increased pulse
- insomnia
- @ sweating
- @ weight loss
- gastrointestinal discomfort
In rare cases, life-threatening cardiovascular complications occur with an overdose. This is especially true if you have untreated nodules in your thyroid gland, for example because they have not yet been detected.
If you are taking antithyroid drugs because of hyperthyroidism, additional iodine administration may undermine the effect of these so-called thyrostatic drugs.
Side effects improve quickly
Because potassium iodide is quickly excreted by the kidneys, the typical symptoms of iodine overdose last only a short time. If the symptoms persist for a longer period of time or even worsen, you should definitely seek medical attention.
Contraindications
You must not take high-dose iodine tablets if you suffer from certain diseases (for example: the rare skin disease dermatitis herpetiformis Duhring or the rare vascular disease hypocomplementemic vasculitis).
Also note that radioiodine therapy for thyroid treatment may lose its effect if iodine tablets are taken at the same time. Also, certain thyroid examination procedures may be negatively affected (thyroid scintigrams, TRH test).
Iodine is an essential component of thyroid hormones. Iodine intake normally occurs through the diet. Some regions are naturally low in iodine. This then also applies to the food grown there and the drinking water. Iodine tablets can then prevent the consequences of an iodine deficiency – for example, the formation of a goiter.
To learn how high-dose iodine tablets for iodine blockade work in a nuclear incident, read the following section.
Iodine blockade by iodine tablets in a nuclear incident
In a nuclear incident, such as one caused by a damaged nuclear power plant, large amounts of radioactive iodine can be released into the environment, which is then absorbed by the body.
The body does not distinguish between radioactive iodine and “normal” iodine and accumulates it in the thyroid gland. The radioactive isotopes can damage the tissues of the thyroid gland through radiation and thus increase the risk of thyroid cancer.
High-dose iodine tablets are intended exclusively for acute disaster situations. You should never take them on your own initiative as a precaution!
Timing of intake is crucial
The time of intake is crucial for the optimal protective effect of high-dose iodine tablets. Ideally, it should be taken about three to six hours before the expected local radioactive exposure.
Taking the tablets too early: if you take them too early, your body will have excreted the excess potassium iodide before it can take effect. In addition, you are stressing your body with the high dose without any benefit.
Taking it too late: If it is taken too late, the effect is also greatly reduced. The iodine blockade is then no longer effective.
As a rule, a single dose is sufficient for iodine blockade, since radioactive iodine isotopes decay after only a few days. In individual cases, however, the competent authority may recommend a further intake of tablets.
High-dose iodine tablets are intended exclusively for acute disaster situations. You should never take them on your own initiative as a precaution!
Timing of intake is crucial
The time of intake is crucial for the optimal protective effect of high-dose iodine tablets. Ideally, it should be taken about three to six hours before the expected local radioactive exposure.
Taking the tablets too early: if you take them too early, your body will have excreted the excess potassium iodide before it can take effect. In addition, you are stressing your body with the high dose without any benefit.
Taking it too late: If it is taken too late, the effect is also greatly reduced. The iodine blockade is then no longer effective.
As a rule, a single dose is sufficient for iodine blockade, since radioactive iodine isotopes decay after only a few days. In individual cases, however, the competent authority may recommend a further intake of tablets.
For whom is iodine blockade useful?
The risk of developing thyroid cancer after exposure to radioactive iodine is higher for children and adolescents than for adults.
Experts estimate that the risk for people older than 45 years is low. The latency period between exposure to radioactive iodine isotopes and subsequent cancer is about 30 to 40 years.
Do high-dose iodine tablets provide comprehensive radiation protection?
No. Taking high-dose iodine tablets only protects against radioactive iodine. They do not provide protection from radioactive radiation or from other dangerous radioactive fission products that may be released into the environment during a nuclear incident. These include, for example, radioactive cesium, strontium and other radiating heavy metals.
