The nuclear emergency in the wake of Japan's devastating earthquake and tsunami has many Americans frightened for their own safety. Some living on the West Coast of the United States are worried about nuclear fallout crossing the Pacific—and are making a run on the potassium iodide (KI) tablets approved by the Food and Drug Administration (FDA) to protect against cancer-causing radiation.

Potassium iodide is a salt that blocks the body from absorbing radioactive iodine, which can be accidentally released from a nuclear reactor. Blocking the absorption of radioative material can reduce the risk for cancer, among other things. Fetuses and infants are especially at risk from radioactive iodine, according to the U.S. Centers for Disease Control & Prevention (CDC), as are young children and anyone with a disorder that causes lower-than-normal amounts of iodine in the thyroid. 

Read more: How Radioactive Iodine Affects the Thyroid Gland

Panic Driving Demand & Price

The Wall Street Journal reports that Anbex Inc., the manufacturer of the iOSAT tablets, continues to get about three orders a minute, up from a typical amount of three orders per week. Anbex has run out of the tablets. Fleming Pharmaceuticals, which makes ThyroShield, reports getting dozens of calls every hour and expects to run out of supply in a week., a major internet supplier of iOSAT iodide tablets (the only brand of FDA-approved pills) and ThyroShield iodide liquid (the only FDA-approved liquid brand) stated on their company Twitter account that they had sold out of both products during the past weekend. has also stated that they have donated 50,000 pills to Tokushukai Hospital in Tokyo for distribution to Japanese citizens.

Meanwhile, on, the same iOSAT potassium iodide pills are currently selling for $250 for a package of 14. The same package normally sells for only $10. On eBay, bidding for potassium iodide is rabid, with recent sales reaching well into the triple digits.

Fear vs. Facts

The speculative mass purchasing seems to be based more on fear than on hard facts; most emergency professionals have stated that it is extremely unlikely that nuclear fallout will cross the more than 5,000-mile expanse of ocean separating Japan and California.

There is no risk, said 17th Surgeon General of the U.S. Dr. Richard Carmona. "Americans should be reassured that they are safe and that there is no reason to stockpile any medications." 

The head of the U.S. Nuclear Regulatory Commission, Gregory B. Jaczko, told the press on Tuesday that "based on the type of reactor design and the nature of the accident, we see a very low likelihood—really, a very low probability—that there's any possibility of harmful radiation levels in the U.S. or in Hawaii." Radiation detectors in California, Oregon, and Washington—which are constantly monitored for even the slightest change—have not indicated any increase in harmful radioactivity.

While the public speaks of the incident in Japan in the same breath as the Chernobyl meltdown of 1986, experts say it is probably closer to the event that took place on Pennsylvania's Three Mile Island reactor in 1979. The Three Mile Island reactor had no noticeable health impacts on local populations, even years later. Experts say that, as with Three Mile Island, the Japanese reactors are unlikely to have serious health effects on local populations, let alone people living in the U.S.

Dr. Carmona confirmed, telling Healthline that "even with the worst-case scenario, it is extremely unlikely that [the radiation] would affect the health of anyone in the U.S." 

Potential Dangers of KI Tablets

And, in fact, taking potassium iodide as a precautionary measure can actually be dangerous. In a public statement, California's Department of Public Health warned that potassium iodide "is not necessary given the current circumstances in Japan, it can present a danger to people with allergies to iodine or shellfish or who have thyroid problems. Taken inappropriately, it can have serious side effects including abnormal heart rhythms, nausea, vomiting, electrolyte abnormalities, and bleeding."

So if you are buying potassium iodide, don't take it without talking to a health professional. "Before you take any medication, you should consult a doctor first, " added Dr. Carmona. "You should never just take potassium idodide, which is an antidote for radiation poisoning, without oversight or guidance from health professionals."

What Can You Do?

"Stockpiling is not a reasonable thing to do," said Dr. Carmona. "The public should be reassured that all our systems are in place, and there is no risk from the Japanese release." 

When asked what the average American should do, Dr. Carmona focused on becoming better educated local and global citizens. "People should be inquisitive," said Dr. Carmona. "They should learn what would happen in their community if something were to occur—whether that's a fire, an earthquake, a flu epidemic, anything. Understand what you can do as an individual, what you should do to protect your family, and what canyouI do to become an asset for your community in times of emergency."