Potassium Iodide Frequently Asked Questions
What is radioactive iodine?
What is Potassium Iodide?
What is the difference between liquid (ThyroShield) and tablet (Iosat) Potassium Iodide?
Will potassium iodide radiation tablets protect me against a "dirty bomb"?
How do I know if there is radiation in my area?
Do I need a prescription?
What about FDA Approval?
What about other Potassium Iodide (KI) products? Or Potassium IodATE?
How much should I buy?
Can I give it to my child easily?
What is the dosage?
When should I take it? When should I stop?
Is it safe? Who should and shouldn't take it?
Can I give it to my pets?
What is the shelf life?
What do the experts say about potassium iodide?
What is radioactive iodine? back to top
One of the most feared consequences of a nuclear reactor accident or nuclear bomb is the release of a radioactive iodine plume into the environment. Radioactive Iodine (I-131) is a by-product of nuclear fission which occurs only within a nuclear reactor or during detonation of a nuclear bomb. What makes radioactive iodine so dangerous is that the body cannot distinguish it from ordinary iodine. As a result, if swallowed (in contaminated food or water), or inhaled (it can remain in the atmosphere for days), it will be absorbed into the thyroid gland (only the thyroid absorbs iodine) and may lead to thyroid cancer, especially in children. The value of Potassium Iodide (KI) tablets were demonstrated following the Chernobyl nuclear accident, where authorities began mass distribution of Potassium Iodide just hours after the explosion. In the years following the accident in areas where people received the drug, the incidence of thyroid cancer has not increased. But where Potassium Iodide was not distributed, previously rare forms of juvenile thyroid cancer have begun appearing at epidemic rates, with over 11,000 known cases. This number continues to rise and is not expected to peak until 2010.
What is Potassium Iodide? (chemical abbreviation is KI) back to top
Potassium Iodide (KI) is used by health officials worldwide to prevent thyroid cancer in people who are exposed to radioactive iodides caused by nuclear reactor accidents and nuclear bombs. It protects against radioactive iodine by preventing its absorption by the thyroid gland located in the neck. Thyroid cells are unique among all cells of the human body as they are the only cells which have the ability to absorb Iodine. The thyroid gland absorbs it from the bloodstream and concentrates it inside the cell to produce hormones. For radiation that is not immediately lethal, the thyroid is your body's most sensitive organ to the effects of radiation. The Radioactive Iodine is absorbed by the thyroid and can cause thyroid disease and cancer later on. Sometimes it only takes a short time if the victim is a child because a child’s thyroid is very active in helping the child to grow. FDA Approved IOSAT and ThyroShield saturates the thyroid with stable iodine, shutting off its absorption mechanism, and it will remain off long enough for the radioactive iodine that you inhaled or ingested to to be safely disbursed through the kidneys. IOSAT KI is the only FDA-approved full strength thyroid blocking tablet available to the public. ThyroShield is the only liquid Potassium Iodide approved by the FDA.
What is the difference between the liquid (ThyroShield) and the tablet (Iosat) Potassium Iodide? back to top
As far as effectiveness and safety for adults or children, there is no difference between the liquid and the tablet. Both are FDA approved, have the same active ingredient (iodine), and can be effectively and safely administered to adults or children. The Iosat has a longer expiration date, is less expensive and is packaged for single-unit dosing. ThyroShield is flavored. An adult could take one Iosat tablet or two droppersful of ThyroShield. A child could take half an Iosat tablet or one dropperful of ThyroShield, etc. If you don't care to quickly crush and dissolve the tablet to administer to a small child then the liquid ThyroShield is your alternative.
Will potassium iodide radiation tablets protect me against a "dirty bomb"? back to top
A "dirty bomb" is a conventional explosive, such as dynamite, salted with radioactive waste that scatters when the bomb goes off. The bomb can kill or injure through the initial blast of the conventional explosive and possibly through the dispersal of the radioactive materials-- hence the term "dirty." Such bombs could be small devices or as big as a truck bomb. There are four categories of radioactive waste ranging from very low-level waste that can be safely disposed of with ordinary refuse, to high-level waste such as spent nuclear fuel. Substantial amounts of radioactive waste are generated through civilian and military applications of radionuclides in medical facilities, food irradiation plants, chemical and manufacturing plants, etc. Some types of radioactive waste would be easier to obtain than others in order to make a "dirty bomb". Radiation detectors are needed to alert officials of their presence. The RADTriage™ personal radiation detector has the technology to detect Gamma, X-ray and Beta radiation. This includes the ability to detect radioactive iodine, of which Potassium Iodide protects against and would most likely not be present in a dirty bomb due to the fact that it is a byproduct of nuclear fission which takes place only within nuclear reactors and during the detonation of a nuclear bomb. Obviously this type of 'radioactive waste' would be very difficult to obtain and incorporate in the makings of a dirty bomb. If a dirty bomb detonates in your area, follow the instructions of local health officials concerning evacuation, decontamination and the administering of potassium iodide (though unlikely).
How do I know if there is radiation in my area? back to top
By using a radiation detector, emergency officials, such as FEMA, can monitor the environment for detectable levels of radiation. One would hope that they are in your area with their equipment as quick as possible and that they report this information to the public immediately. Of course, they cannot follow you and your family around with their detectors and tell you if you specifically have retreated to a safe environment away from the radiation. A back-up to the reliance on emergency officials, such as FEMA, would be the possession of a personal radiation detector to alert you to harmful levels of gamma, beta and x-ray radiation.
Do I need a prescription? back to top
Because of the inherent safety of Potassium Iodide that is FDA Approved, it is available without a prescription for radiation protection. Its use, however, should be limited to radiation emergencies and only when recommended by emergency response authorities.
What about FDA Approval? back to top
IOSAT Potassium Iodide is the only full strength brand tested and approved by the FDA for radiation emergencies. ThyroShield is the only liquid Potassium Iodide approved by the FDA. Ask yourself - If you had cancer and could take a drug that would cure it, would you take an FDA regulated and approved drug, or a non-approved drug? Then ask - If you could take a pill to possibly prevent cancer would you take an FDA Approved drug or a non-approved drug? Rad Block™, Life-Extension (LEF), I.A.A.A.M. and Potassium IodATE (different spelling, different drug) are not FDA Approved for radiation emergencies.
The 1997 Federal Food, Drug and Cosmetic Act states that: "No person shall introduce or deliver for introduction into interstate commerce any new drug, unless an approval filed pursuant to subsection (b) or (j) of this section is effective with respect to said drug".
To verify what brands of Potassium Iodide (or any drug) have FDA approval click on this link for the Orange Book at the FDA Center for Drug Evaluation and Research. Type in Potassium Iodide, click on "OTC" and then "submit".
What about other Potassium Iodide (KI) products? Or Potassium IodATE? Are they FDA approved?
back to top
Rad Block, I.A.A.A.M., No-Rad, Life Extension (LEF), KI4U, NukeProtect, ProKI and KIO3 Potassium IodATE (different spelling, different drug) are not FDA Approved for radiation emergencies. The FDA has sent cease and desist letters to some of these manufacturers who recommend their product for radiation emergencies. Other products (like Rad Block) state they are manufactured in an "FDA licensed and approved over-the-counter (OTC) drug manufacturing facility". Well, the facility might be FDA licensed but their Potassium Iodide is not mandated under strict FDA “GMP guidelines,” nor do they hold an approved “New Drug Application” (NDA) for KI (Potassium Iodide). The incoming raw materials and outgoing Potassium Iodide pills are not approved by the FDA. (During a nuclear emergency would you want to give your family a non-FDA-approved drug that cost more?)
But they say they were registered with the FDA and have a National Drug Code (NDC) number to prove it! The NDC serves as a universal product identifier for human drugs. An NDC number does not indicate that a drug is FDA approved. FDA’s regulation at 21 C.F.R.207.39 specifically states that: "registration of a drug establishment or drug wholesaler, or assignment of a registration number, or assignment of a NDC number does not in any way denote approval of the firm or its products. Any representation that creates an impression of official approval because of registration or possession of registration number or NDC number is misleading and constitutes misbranding". Instead, drug approval involves a completely different process, which includes the submission by a manufacturer of a new drug application (NDA) or an abbreviated new drug application (ANDA), which FDA then may approve - International Academy of Compounding Pharmacists.
More info can be found here on our website at Potassium Iodate vs Potassium Iodide
How much should I buy? back to top
We recommended one Iosat pack or one ThyroShield bottle per person for storing at home. Each Iosat pack has 14 130mg tablets. A two week supply for an adult and a 28+ day supply for a child. One ThyroShield bottle has 30ml, a 15 day supply for an adult or month+ supply for a child. However, you should consider stocking Potassium Iodide outside the home as well. You wouldn't want to get caught without Potassium Iodide if something should happen. Can you imagine the traffic jam as everyone leaves town at the same time?
Can I give it to my child easily? back to top
A whole Iosat pill is the size of a baby aspirin and is scored for easy and exact separation for half and quarter dosages if desired. For children who won't swallow pills, follow this FDA link on administering potassium iodide to children. Black raspberry flavored liquid ThyroShield is easy to administer to children with the use of the enclosed dropper.
What is the dosage? back to top
On December 10, 2001 the FDA released a guidance on potassium iodide. The guidance issued is not just for the 10-mile Emergency Planning Zone, but for any and all areas potentially affected. Close in, there may not be time to deal with fractional dosage of Potassium Iodide (see below). The guidance acknowledges that strict adherence to the age-related dosing guidelines may be difficult to achieve and, therefore, emphasizes that across populations at risk for radioiodine exposure, the overall benefits of potassium iodide far exceed the risks of overdosing, especially in children, though particular attention should be paid to dose and duration of treatment in infants and in pregnant women.
Iosat Consumer Package Insert
One dose every 24 hours. Take one dose as soon as possible and then every 24 hours at the same time each day. Take potassium iodide only when exposed to radioactive iodine as notified by state or local public health officials. Pills are double-scored for easy separation is desired. Follow this FDA Guideline for administering to young children if desired.
Age 18+* -----------130mg daily (One IOSAT tablet)
Age 3 - 18 -----------65mg daily (1/2 IOSAT tablet) - Adolescents approaching adult size should receive the full adult dose (130 mg).
1 month - 3 yrs. ----- 32mg daily (1/4 IOSAT tablet)
Birth - 1 month ----- 16mg daily (1/8 IOSAT tablet)
ThyroShield Consumer Package Insert
|Adults over 18 years
||2 mL every day (130 mg)
|Children over 12 years to 18 years who weigh at least 150 lbs.
||2 mL every day (130 mg)
|Children over 12 years to 18 years who weigh less than 150 lbs
||1 mL every day (65 mg)
|Children over 3 years to 12 years
||1 mL every day (65 mg)
|Children over 1 month to 3 years
||0.5 mL every day (32.5 mg)
|Babies at birth to 1 month
||0.25 mL every day (16.25 mg)
When should I take it? When should I stop? back to top
For optimal protection against inhaled radioiodines, Potassium Iodide should be administered before the passage of the radioactive iodine plume, though Potassium Iodide may still have a substantial protective effect even if taken 3 or 4 hours after exposure. Take one dose as soon as possible and then every 24 hours at the same time each day. Take potassium iodide only when exposed to radioactive iodine as notified by state or local public health officials. Furthermore, if the release of radioiodines into the atmosphere is protracted, then, of course, even delayed administration may reap benefits by reducing, if incompletely, the total radiation dose to the thyroid. As time is of the essence in optimal prophylaxis with Potassium Iodide, timely administration to the public is a critical consideration in planning the emergency response to a radiation accident and requires a ready supply of Potassium Iodide. Potassium Iodide has no impact on the uptake by the body of other radioactive materials and provides no protection against external irradiation of any kind. FDA emphasizes that the use of Potassium Iodide should be as an adjunct to evacuation (itself not always feasible), sheltering, and control of food stuffs.
Is it safe? Who should and shouldn't take it? back to top
Potassium iodide is extremely safe in the dosage provided by IOSAT and ThyroShield. Because it is widely used in other treatments, its effects are well known. Calculations by the National Council on Radiation Protection suggest that the incidence of adverse reactions to Potassium Iodide can be as low as 1 in 10 million, and often no more than a mild skin rash. In the 1930s the government required salt manufacturers to add Potassium Iodide to its table salt (like Morton salt) because people in the great lakes region had iodine-deficient diets and had a high rate of goiters and other thyroid problems. Potassium Iodide is also added to children's Flintstone vitamins because it is an essential mineral. It has also been used as a children's expectorant for years.
Repeat dosing of Potassium Iodide should be avoided in the neonate to minimize the risk of hypothyroidism during that critical phase of brain development. As stated above, we recommend that neonates (within the first month of life) treated with Potassium Iodide be monitored for the potential development of hypothyroidism and that thyroid hormone therapy be instituted in cases in which hypothyroidism develops. Pregnant women should be given Potassium Iodide for their own protection and for that of the fetus, as iodine (whether stable or radioactive) readily crosses the placenta. However, because of the risk of blocking fetal thyroid function with excess stable iodine, repeat dosing with Potassium Iodide of pregnant women should be avoided. Lactating females should be administered Potassium Iodide for their own protection, as for other young adults, and potentially to reduce the radioiodine content of the breast milk, but not as a means to deliver Potassium Iodide to infants, who should get their Potassium Iodide directly. As for direct administration of Potassium Iodide, stable iodine as a component of breast milk may also pose a risk of hypothyroidism in nursing neonates. Therefore, repeat dosing with Potassium Iodide should be avoided in the lactating mother, except during continuing severe contamination. If repeat dosing of the mother is necessary, the nursing neonate should be monitored as recommended above.
Pregnant women should take it for their own protection and for that of the fetus, as iodine (whether stable or radioactive) readily crosses the placenta. However, because of the risk of blocking fetal thyroid function with excess stable iodine, repeat dosing with Potassium Iodide of pregnant women should be avoided. Lactating females should be take it for their own protection to reduce the radioiodine content of the breast milk, but not as a means to deliver Potassium Iodide to infants, who should get their Potassium Iodide directly.
From the FDA - "Short-term administration of KI (Potassium Iodide) at thyroid blocking doses is safe and, in general, more so in children than adults. The risks of stable iodine administration include sialadenitis (an inflammation of the salivary gland, of which no cases were reported in Poland among users after the Chernobyl accident), gastrointestinal disturbances, allergic reactions and minor rashes. In addition, 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. Thyroidal side effects of stable iodine include iodine-induced thyrotoxicosis, which is more common in older people and in iodine deficient areas but usually requires repeated doses of stable iodine. In addition, iodide goiter and hypothyroidism are potential side effects more common in iodine sufficient areas, but they require chronic high doses of stable iodine. In light of the preceding, individuals with multinodular goiter, Graves' disease, and autoimmune thyroiditis should be treated with caution, especially if dosing extends beyond a few days. The vast majority of such individuals will be adults. The transient hypothyroidism observed in 0.37 percent (12 of 3214) of neonates treated with KI in Poland after Chernobyl has been without reported sequelae to date. There is no question that the benefits of KI treatment to reduce the risk of thyroid cancer outweigh the risks of such treatment in neonates. Nevertheless, in light of the potential consequences of even transient hypothyroidism for intellectual development, we recommend that neonates (within the first month of life) treated with KI be monitored for this effect by measurement of TSH (and FT4, if indicated) and that thyroid hormone therapy be instituted in cases in which hypothyroidism develops".
Can I give it to my pets? back to top
There have been no studies concerning animals and the administration of Potassium Iodide for radiation emergencies. Like humans, animals do not normally have any allergic reaction to limited doses of Potassium Iodide. For animals with no known iodine allergies (ask your vet) it is a relatively safe drug. If you wish to administer potassium iodide to your pet, follow the Iosat dosing chart amounts listed above in the "What is the dosage?" info and give the appropriate dosage based upon weight. For instance, the dosage for a 2-year-old child would be 32mg (1/4 tablet). If an average 2-year-old weighs 25 -30 lbs., a dog weighing the same would take the same dosage, 32mg (1/4 tablet). If a 2-week-old infant weighs on average 9 pounds, then you would give a 9 pound cat/dog 16mg (1/8 tablet). Crush it up and put it in their food. Please consult with a vet in advance to make sure your pet can safely take Potassium Iodide.
Note: Iodine is found in table salt, fish oil, kelp, daily vitamins, etc.)
What is the shelf life? back to top
7 year shelf-life from date of manufacture for IOSAT.
5 year shelf-life from date of manufacture for ThyroShield.
What do the experts say about potassium iodide? back to top
Many authorities on radiation exposure and thyroid cancer have made
statements about the benefits of Potassium Iodide following a nuclear accident.
American Academy of Pediatrics
April 3, 2003 News Release - "The American Academy of Pediatrics (AAP) recommends that households within 10 miles of a nuclear power plant keep potassium iodide (KI) on hand to protect the thyroid in the event of an accidental or intentional release of radioactive iodines ("radioiodines") into the environment. Schools and child care facilities within the same radius also should have immediate access to KI. It may be prudent to consider stockpiling KI within a larger radius because of more distant windborne fallout".
Dept of Homeland Security - Ready.gov
"Consider keeping potassium iodide in your emergency kit, learn what the appropriate doses are for each of your family members".
FEMA - Nuclear Power Plant Preparedness Document
"The thyroid gland is vulnerable to the uptake of radioactive iodine. If a radiological release occurs at a nuclear power plant, States may decide to provide the public with a stable iodine, potassium iodide, which saturates the thyroid and protects it from the uptake of radioactive iodine. Such a protective action is at the option of State, and in some cases, local government".
In December 2001, the Food and Drug Administration released their final guidance on Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies. Quote - "FDA maintains that KI is a safe and effective means by which to prevent radioiodine uptake by the thyroid gland, under certain specified conditions of use, and thereby obviate the risk of thyroid cancer in the event of a radiation emergency". FDA December 2001
World Health Organization
In 1999 the World Health Organization (WHO) updated their Guidelines for Iodine Prophylaxis Following Nuclear Accidents. Quote - "Stable iodine administered before, or promptly after, intake of radioactive iodine can block or reduce the accumulation of radioactive iodine in the thyroid. Intake of radioactive iodine by inhalation begins when the radioactive cloud arrives at a location and continues during the passage of the cloud. Action to implement stable iodine prophylaxis, and thereby reduce the dose to the thyroid, will be required promptly". WHO 1999 This link opens as a pdf file so you will need Acrobat Reader installed on your computer to view it. You may download this handy program for free by clicking here.
Nuclear Regulatory Commission (NRC)
"The Nuclear Regulatory Commission (NRC) is amending its emergency planning regulations governing the domestic licensing of production and utilization facilities. The final rule requires that consideration be given to including potassium iodide (KI) as a protective measure for the general public that would supplement sheltering and evacuation. KI would help prevent thyroid cancers in the unlikely event of a major release of radioactivity from a nuclear power plant". - NRC January 2001
Remarks on the need for potassium iodide made by Commission Chairman Nils Diaz of the Nuclear Regulatory Commission on 11/10/2001..."use of potassium iodide pills would have significantly reduced the incidence of thyroid cancer [during Chernobyl]".
"At last count, some 1,800 children in the former Soviet Union have developed thyroid cancer as a result of the [Chernobyl] accident. Almost all were very young-in the womb or under 2 years old-at the time of exposure. In adults, thyroid cancer is usually slow-growing, but in the Chernobyl children, it has proved to be aggressive. In more than two-thirds of cases, the malignancy has spread beyond the thyroid by the time of surgery. The disease has a long latency period, so thousands more cases are expected in coming decades". - in a letter from Peter G. Crane, former attorney for the Nuclear Regulatory Commission.
The American Thyroid Association
In November 2001, The American Thyroid Association endorsed the usage of Potassium Iodide for Radiation Emergencies. "The American Thyroid Association endorses the federal Nuclear Regulatory Commission's December 2000 action requiring states and the Federal Emergency Management Agency to look into having potassium iodide (KI) stockpiled and available for populations at risk for exposure to radioactive iodine from a nuclear emergency." - ATA November 30, 2001
"A radius of 20 miles [KI distribution around nuclear plants] is required by the Bioterrorism Act of 2002 (P.L.107-188) but this is much too restricted in light of the Chernobyl experience". - In response to the National Academy of Sciences Study of Strategies for KI Distribution and Administration.
"...both an expert committee of the National Academy of Sciences and the American Thyroid Association endorse the use of KI and have confidence in its safety..." - Letter from ATA President to Department of Health and Human Services, Washington, D.C.
"The seminal event that opened the world’s eyes to the importance of KI distribution was the 1986 Chornobyl nuclear accident, releasing a fallout cloud that spread radioactive iodine and other radionuclides throughout eastern and central Europe. Starting a few years later, infants and children who had been exposed to the fallout were diagnosed with an unusual and aggressive form of thyroid cancer, except in Poland where the government had distributed KI pills". From an ATA news summary titled, Experts Discuss Potassium Iodide Distribution in Case of Nuclear Incident (PDF document)
Public Citizen is a national, nonprofit consumer advocacy organization founded in 1971 to represent consumer interests in congress, the executive branch and the courts. Their website covers are aspects of consumer protection including their statement on The NRC's Failure to Stockpile Potassium Iodide & Protect the Public Health and Safety. "For over 25 years, the use of blocking agents such as potassium iodide to prevent the accumulation of radioiodine in the thyroid gland has been known. The effectiveness of potassium iodide administration for thyroid gland protection in the event of releases of radioiodine was recognized by the National Council on Radiation Protection and Measurement in 1977. The Food and Drug Administration authorized use of potassium iodide as a thyroid-blocking agent for the general public in December 1978." - Public Citizen 2001
Union of Concerned Scientists
The Union of Concerned Scientists is a nonprofit partnership of scientists and citizens combining rigorous scientific analysis, innovative policy development and effective citizen advocacy to achieve practical environmental solutions. Read their release entitled, "Precaution for Nuclear Accident a Stitch in Time That Saves Way More Than Nine". Quote - "A January decision is expected by the Commissioner of Public Health for the State of Massachusetts on whether to recommend that potassium iodide be stockpiled to protect public health in event of an accident at a nuclear facility. The Union of Concerned Scientists joins many others from the environmental and medical communities in urging the Commissioner, Dr. Howard Koh, to recommend this crucial precaution." - Union of Concerned Scientists December 22, 1999
Twenty three years after Chernobyl:
What's been learned, What's been ignored
A Proposal to Stockpile and Distribute Potassium Iodide