The U.S. Food and Drug Administration said Thursday there is no current need to take potassium iodide pills because of the recent leak of nuclear material in Japan.

Potassium Iodide (KI) blocks the thyroid gland from absorbing Iodine-131, the harmful element produced by nuclear radiation.

Pharmacies in the United States have been selling out of the drug this week, as people stock up on it, even though no radiation from the damaged Japanese reactors has been detected in the U.S. and experts say there is little chance any fallout could spread across the Pacific Ocean.

The FDA said it is aware that this run on potassium iodide has created a shortage of the drug. And, while it says it is working with companies approved to sell KI to make the pills more widely available, it stressed there is no need to take them at this time.

“There is no public health event requiring anyone in the U.S. to take KI because of the ongoing situation in Japan,” the FDA states.  Potassium iodide can also be harmful to some people, such as those who have thyroid problems, and can cause allergic reactions.

Because of the shortage of pills, however, the FDA cautioned consumers not to turn to  Internet sales and other retail outlets that may be peddling fraudulent products or “making false claims to prevent or treat effects of radiation or products that are not FDA-approved.”

Those could include supplements or foods made from seaweed or kelp that contain iodine.

It warned people to beware of possible fraudulent products and:

— Claims that a product not approved by FDA can prevent or treat harmful effects of radiation exposure

—  Suggestions that a KI product will treat conditions other than preventing the uptake of radioactive molecules

— Promotions using words such as “scientific breakthrough,” “new product,” “miraculous cure,” “secret ingredient,” and “ancient remedy”

—  Testimonials from consumers or doctors claiming amazing results

—  Limited availability and advance payment requirements

—  Promises of no-risk, money-back guarantees

—  Promises of an “easy” fix

—  Claims that a product is “natural” or has fewer side effects than approved drugs

The three manufacturers currently approved by the FDA to sell potassium iodide in the United States are Anbex, Inc., Fleming & Co. Pharmaceuticals, and Recipharm AB.

In light of the shortage of KI  pills, there are concerns that some people may try eating iodized salt as another remedy to protect against the negative effects of radiation.

That prompted the Salt Institute to warn that this is not an effective method for stopping absorption of nuclear material in the thyroid. It says there is not enough iodine in the salt to stop the thyroid from being able to absorb harmful particles.

To reach the level of iodine contained in a tablet of potassium iodide, a person would need to consume 3 ½ pounds of iodized salt, the Salt Institute said in a news release.