Should you buy potassium iodide (KI) tablets to counteract possible radiation exposure?
Although the role of KI pills has been discussed for decades, many people still don’t know the guidelines for stocking or taking them, says Richard T. Kloos, MD, Chief Operating Officer of the American Thyroid Association (ATA).
“There’s no reason that the American public should take these now.” However, this issue surpasses the current situation in Japan.”
“We would like the American public to be knowledgeable and informed, but now is not the time for Americans to panic,” Dr. Kloos says. “I don’t think the American public is at any risk, and I don’t think they should be taking any prophylaxis unless a reliable source tells them to do so.”
Potential Side Effects of KI pills
Although KI is considered very safe (the iodine is the same as that found in table salt) clinicians should make patients aware of the rare but real risks, says Dr. Kloos, Co-Director of The Ohio State University Thyroid Cancer Unit in Columbus, Ohio.
Allergic reactions are always a concern.
“When large populations took potassium iodide in Poland after Chernobyl, it was shown to be quite safe,” he says.
“But small numbers of people did experience things like skin rashes, abdominal discomfort, and vomiting.”
In addition, the same process that makes iodine protective in radiation exposure can also alter thyroid function in the longer term. The thyroid acts like a sponge in the presence of iodine, so saturating it with regular iodine prevents the uptake of radioactive iodine found in nuclear fallout.
If someone continues to take KI pills over a period of time, the thyroid may shut down and the person may develop hypothyroidism, Dr. Kloos says. Alternatively, people with overactive thyroids could also develop complications.
“Iodine is a fuel for our thyroids,” Dr. Kloos says. “If you dump in fuel, some people could exacerbate their hyperthyroidism.”
The main take-away point to give patients, says Dr. Kloos, is that if there’s no benefit from KI supplementation, as in the absence of radiation exposure, then even these low-level risks are unacceptable. Given the vast distance that any radiation from Japan would have to travel, US residents have no cause for concern.
KI’s Role in Overall Response
The larger issue is whether people should stock KI pills in the event that they are exposed to radiation. The controversy stems from several issues, including:
disagreements about how large an area would be affected quickly in the event of a nuclear accident; concerns that widespread distribution of KI pills would give people a false sense of security, given that the pills only protect against thyroid cancer and not against other radionuclides or other body organs; and concerns that a wider distribution would undermine the public’s confidence in the safety of nuclear power.
The US Nuclear Regulatory Commission provides KI pills to states with nuclear power plants, enabling (but not requiring) them to distribute the pills to residents within 10 miles of a plant. In 2002, Congress ordered that the distance be extended to 20 miles, but in 2008 the Bush Administration invoked a waiver to override that provision. The new ruling said that the 10-mile radius was adequate because the primary focus would be on evacuation and avoidance of contaminated food and water.
In contrast, the ATA’s position since 1984 has been that KI pills should be distributed to households within 50 miles of a nuclear power plant and should be available to those within a 200-mile radius. In fact, it cites evidence from the Chernobyl nuclear accident to support its position:
After the 1986 Chornobyl (formerly called “Chernobyl”) nuclear accident, shifting winds blew a radioactive cloud all over Europe. As many as 3,000 people exposed to that radiation have already developed thyroid cancer. Most victims had been babies or young children living in Ukraine, Belarus, or Russia at the time of the accident. According to a UN report released in February 2002, another 8,000 to 10,000 exposed people may develop thyroid cancer within the next 10 years. Poland, immediately adjacent to Belarus and Ukraine, distributed KI to its people and does not appear to have had an increase in thyroid cancer.
“We think the disaster zone for a drug that is potentially cancer preventive with limited side effects — and one that is hard to distribute after a disaster — needs to be distributed beforehand to people within 50 miles,” says Dr. Kloos. The ATA supports the focus on evacuation but still believes that KI pills can be an important part of an evacuation plan if distributed before a disaster takes place.
“Because of the panic and infrastructure disruption that can occur, getting away is not as easy as one might think it is,” Dr. Kloos says. “We saw how hard it was to get away from Hurricane Katrina.” People in radiation-disaster areas could at least have some protection with KI pills while they implement their evacuation plans if they stocked the pills ahead of time.
In fact, Dr. Kloos believes that it is reasonable for anyone to keep a supply of KI pills in their homes. But, he says, there is no reason for anyone right now to rush out and buy them or to pay higher prices from distributors who are cashing in on current fears. His advice today is the same as it was a week ago, or even years ago, when it generally fell on deaf ears. He hopes that the heightened interest spurred by the situation in Japan will lead to better awareness of the facts, especially among clinicians.
Reprinted from http://bit.ly/hOaJGV