Potassium Iodide Tablets Shelf Life

November 13, 2015, by Ken Jorgustin


In case you have been wondering about the shelf life of potassium iodide tablets, also branded as iOSAT, I discovered that what I had thought about it has been incorrect…

For those of you who don’t know what they are, they’re basically ‘nuke pills’ that help prevent radioactive iodine from getting into the thyroid gland during a nuclear radiation emergency.
You do have some, right?

Here’s what I discovered about their shelf life:

I always keep several packs of iOSAT (Potassium Iodide Tablets, 130mg) on hand as part of my medical preps. Although I do not live near any nuclear power plants, it’s still cheap insurance to have on hand. There’s also that little threat called nuclear war – which may not be so little…

As with all types of ‘medications’, there is an expiration date printed on the package. While I generally know that in many or most cases these dates do not mean that the drug will ‘go bad’ the next day, in fact, many drugs/medications will be quite effective for significantly longer (do your own due-diligence).

With that said, we were recently going through our medical / First Aid supplies and I came across the packets of iOSAT potassium iodide tablets (which supposedly expired in 2013). I decided to do some research on it, and guess what I found out? They are still good!

From the United States Nuclear Regulatory Commission, FAQ,

Is it safe to take KI tablets with an expired shelf-life?

(KI is potassium iodide)

Quote, “Yes, potassium iodide tablets are inherently stable and do not lose their effectiveness over time.” “Manufacturers must label their products with a shelf-life to ensure that consumers purchase safe and useful products.”

“According to FDA guidance on Shelf-life Extension, studies over many years have confirmed that none of the components of KI tablets, including the active ingredient, has any significant potential for chemical degradation or interaction with other components or with components of the container closure system when stored according to labeled directions. To date, the only observed changes during stability (shelf-life) testing have been the failure of some batches of KI tablets to meet dissolution specifications. Some tablets tested required slightly longer than the specified time to achieve dissolution. Even in the case of a failure of this sort, the product remains usable.”

So apparently and evidently, iOSAT tablets (or other potassium iodide tablets) do not expire…

Source: NRC


What is potassium iodide?

Potassium iodide is a salt, similar to table salt. Its chemical symbol is KI. It is routinely added to table salt to make it “iodized.” Potassium iodide, if taken in time and at the appropriate dosage, blocks the thyroid gland’s uptake of radioactive iodine and thus could reduce the risk of thyroid cancers and other diseases that might otherwise be caused by exposure to radioactive iodine that could be dispersed in a severe nuclear accident.

When potassium iodide is ingested, it is taken up by the thyroid gland. In the proper dosage, and taken at the appropriate time, it will effectively saturate the thyroid gland in such a way that inhaled or ingested radioactive iodines will not be accumulated in the thyroid gland.