Potassium Iodide (KI)... Frequently Asked Questions

The recommendations in the guidance address KI dosage and the projected radiation exposure at which the drug should be used. This guidance updates FDA’s 1982 recommendations.

In December 2001, the Food and Drug Administration (FDA) issued a final Guidance on Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies (PDF - 40KB).

The objective of the document is to provide guidance to other Federal agencies, including the Environmental Protection Agency (EPA) and the Nuclear Regulatory Commission (NRC), and to state and local governments regarding the safe and effective use of potassium iodide (KI) as an adjunct to other public health protective measures in the event that radioactive iodine is released into the environment.

The adoption and implementation of the recommendations are at the discretion of the state and local governments responsible for developing regional emergency-response plans related to radiation emergencies.

What does potassium iodide (KI) do? Can potassium iodide (KI) be used to protect against radiation from bombs other than radioactive iodine? Who really needs to take potassium iodide (KI) after a nuclear radiation release? What potassium iodide (KI) products are currently available?

How are these products available?

What dosages of  potassium iodide (KI) should be taken for specific exposure levels? How long should potassium iodide (KI) be taken? Who should not take potassium iodide (KI) or have restricted use? What are the possible risks and side effects of taking potassium iodide (KI)? Should I check with my doctor first? As a doctor, should I be recommending potassium iodide (KI) for my patients who request it? Should I go out and buy potassium iodide (KI) to keep on hand? How do I know that potassium iodide (KI) will be available in case of an emergency?

1.  What does potassium iodide (KI) do?

The effectiveness of KI as a specific blocker of thyroid radioiodine uptake is well established. When administered in the recommended dose, KI is effective in reducing the risk of thyroid cancer in individuals or populations at risk for inhalation or ingestion of radioiodines. KI floods the thyroid with non-radioactive iodine and prevents the uptake of the radioactive molecules, which are subsequently excreted in the urine.

2.  Can potassium iodide (KI) be used to protect against radiation from bombs other than radioactive iodine?

Potassium iodide ( KI) works only to prevent the thyroid from uptaking radioactive iodine. It is not a general radioprotective agent.

3.  Who really needs to take potassium iodide (KI) after a nuclear radiation release?

The FDA guidance prioritizes groups based on age, which primarily determines risk for radioiodine-induced thyroid cancer. 

Those at highest risk are infants and children, as well as pregnant and nursing females, and the recommendation is to treat them at the lowest threshold (with respect to predicted radioactive dose to the thyroid). 

Anyone over age 18 and up to age 40 should be treated at a slightly higher threshold. 

Finally, anyone over 40 should be treated with KI only if the predicted exposure is high enough to destroy the thyroid and induce lifelong hypothyroidism (thyroid deficiency).

4.  What potassium iodide (KI) products are currently available? 

As of January 2005, Iosat, ThyroSafe, and ThyroShield are FDA approved KI products. You can find out more about these products at Drugs@FDA.

Please be aware that only the KI products approved by FDA may be legally marketed in the United States.

5.  How are these products available?

In addition to distributing to state, local and federal agencies, Anbex, Inc., has made Iosat Tablets (130 mg) available to the general public via the Internet.

For further information on KI products, you can contact these companies as noted below:

6.  What dosages of potassium iodide (KI) should be taken for specific exposure levels?

FDA recommends the following dosing of KI for thyroid blocking:

Threshold Thyroid Radioactive Exposures and
Recommended Doses of KI for Different Risk Groups

Predicted Thyroid gland exposure (cGy)KI dose (mg)     Number or fraction of 130 mg tabletsNumber or fraction of 65 mg tabletsMilliliters (mL) of oral solution, 65 mg/mL***Adults over
18 through 40 yearsAdolescents,
12 through
18 years*Children over
3 years through 12 yearsChildren 1
month through 3 yearsInfants birth through 1
month

*     Adolescents approaching adult size (> 150 lbs) should receive the full adult dose (130 mg)

**   Potassium iodide oral solution is supplied in 1 oz (30 mL) bottles with a dropper marked for 1, 0.5, and 0.25 mL dosing.  each mL contains 65 mg potassium iodide.

*** See the Home Preparation Procedure for Emergency Administration of Potassium Iodide Tablets to Infants and Small Children.

7.  How long should potassium iodide (KI) be taken?

Since KI protects for approximately 24 hours, it should be dosed daily until the risk no longer exists. 

Priority with regard to evacuation and sheltering should be given to pregnant females and neonates because of the potential for KI to suppress thyroid function in the fetus and neonate. 

Unless other protective measures are not available, we do not recommend repeat dosing in pregnant females and neonates.

8.  Who should not take potassium iodide (KI) or have restricted use?

Persons with known iodine sensitivity should avoid KI, as should individuals with dermatitis herpetiformis and hypocomplementemic vasculitis, extremely rare conditions associated with an increased risk of iodine hypersensitivity.

Individuals with multinodular goiter, Graves' disease, and autoimmune thyroiditis should be treated with caution -- especially if dosing extends beyond a few days.

9.  What are the possible risks and side effects of taking potassium iodide (KI)?

Thyroidal side effects of KI at recommended doses rarely occur in iodine-sufficient populations such as the U.S.

As a rule, the risk of thyroidal side effects is related to dose and to the presence of underlying thyroid disease (e.g., goiter, thyroiditis, Graves'). 

FDA recommends adherence to the Guidance on Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies (PDF - 40KB) for intervention threshold and dose, though we recognize that the exigencies of any particular emergency situation may mandate deviations from those recommendations.

With that in mind, it should be understood that as a general rule, the risks of KI are far outweighed by the benefits with regard to prevention of thyroid cancer in susceptible individuals.

10.  Should I check with my doctor first?

Potassium iodide (KI) is available over-the-counter (OTC).  However, if you have any health concerns or questions, you should check with your doctor.

11.  As a doctor, should I be recommending potassium iodide (KI) for my patients who request it?

As with any drug, physicians should understand the risks and benefits of KI before recommending it or prescribing it to patients.

We recommend that physicians read our guidance for more information. It is available on the FDA Drug Guidances web page, under procedural guidance #18.

The FDA guidance discusses the rationale and methods of safe and effective use of KI in radiation emergencies. It specifically addresses threshold predicted thyroid radioiodine exposure for intervention and dosing by age group.

The recommendations for intervention are based on categories of risk for thyroid cancer, with the young prioritized because of increased sensitivity to the carcinogenic effects of radioiodine.

12.  Should I go out and buy potassium iodide (KI) to keep on hand?

KI works best if used within 3-4 hours of exposure.

Although FDA has not made specific recommendations for individual purchase or use of KI, the Nuclear Regulatory Commission has contracted to purchase KI for states with nuclear reactors and states that have population within the 10-mile emergency planning zone, e.g., Delaware or West Virginia.

13.  How do I know that potassium iodide (KI) will be available in case of an emergency?

FDA will continue to work with interested pharmaceutical manufacturers to assure that high quality, safe, and effective KI products are available for purchase by consumers, by state and local authorities, and by federal government agencies electing to do so.

March 18, 2011 - FDA

Submitted by SadInAmerica on Sat, 03/19/2011 - 1:00pm.

View the original article here

WHEN ASKED TO MAKE A CHEQUE OUT TO CASH, TAKE IT WITH A PINCH OF SALT

the entire anti-salt industry is a huge conglomerate consisting of ... one very sad geezer with a longstanding fixation.

I looked into CASH a while ago and vaguely remembered that they received paltry income while paradoxically enjoying huge media interest. It also struck me that they were working out of someone's office in Tooting.

That someone didn't concern me at the time ...

Prof Graham MacGregor, of St George's Hospital, in Tooting, South-West London, welcomed the move but added: "Why do they need to put salt on the chips at all? Why not leave them as they are and let customers sprinkle on what they want?"

Hmm, interesting.

But the BBC article says he is from the "Wolfson Institute of Preventive Medicine".

Funny enough, so now is the HQ of CASH.

Principal address:

Wolfson Institute of Preventive Medicine,

Charterhouse Square,

London ECIM 6BQ

So it would seem that this entire organisation consists of Graham MacGregor and, err, a couple of mates.

     I completely understand the Food Standards Authority funding them - this is standard fakecharity procedure where an empire building government department pays a fakecharity who then propagandise for a bigger, more powerful and more parasitic government department. That is how British government is run. But why on earth does Nissan, a car company, want to fund a false salt scare story?

      The only thing I can think of is, other than the chief executive being scared by a salt cellar, is that when setting up in Britain they made a discrete promise to make "charitable" donations to funds suggested by various politicians. Perhaps somebody else has some ideas.

     I'll leave the last word on the ridiculousness of this particular health-fascist scare story from Professor John Brignal's Numberwatch

Here we go again! The food fascists are back on the salt trail. A press release from a branch of the Nanny State that calls itself the Food Commission was picked up by all the UK media. They harangue the processed food industry for failing sufficiently to reduce the salt content of their products. There is, of course, a maximum recommended level, based on no scientific evidence at all. The justification comes in the last two lines:

Eating high levels of salt is linked to high blood pressure, which is the main cause of strokes and a major factor in heart attacks, two of the most common causes of death and illness in the UK.

Not only is this based on a familiar form of weasel words “is linked to”, but the story is all about 1 to 6 year olds. We are not told how many of these die of strokes and heart attacks.

The BBC in its enthusiastic promotion of the new scare links to its own essay on salt, which relies on more tame weasel words “Many scientists believe this process is linked to high blood pressure, or hypertension, which in turn is linked to a greater risk of coronary heart disease and stroke.”

In fact, the whole salt farrago has become the epitome of junk science. Gary Taubes has provided a monumental survey of the evidence. It is all there – exaggerations, statistical fiddles, ex cathedra pronouncements, subreption, bullying and an adherence to the principles of religion rather than of science.

The physiological fact is that the human body deals very effectively with the maintenance of its salt balance. Any excess is successfully excreted by action of elaborate control mechanisms. What it cannot deal with is a lack of salt, since it cannot manufacture it. Both sodium and chlorine are essential to huge range of functions within the body, from digestion to nerve impulse transmission. The trick by which animals were able to leave the salt sea was to take it with them in the blood plasma. Animals instinctively know the importance of salt, which is why they resort to salt licks.

View the original article here