A drug used as a preventative measure against radiation is flying off the shelves in California amidst conflicting information from public health officials on whether or not Japan's nuclear crisis poses a threat to the West coast.

"It's a precaution," U.S. Surgeon General Regina Benjamin told a television reporter Tuesday when asked whether citizens stocking up on potassium iodide, an over-the-counter drug that shields the thyroid from radiation, are taking "extreme" measures. "I haven't heard that, but it is a precaution."

But if Benjamin seemed to tacitly approve of residents buying up potassium iodide, a spokesperson for the Department of Health and Human Services clarified the remark to Fox News on Thursday. "She commented that it is always important to be prepared, however, she wouldn't recommend that anyone go out and purchase [potassium iodide] for themselves at this time," Dori Salcido said. "It's important for residents who have concerns to listen to state and local health authorities."

California public health officials Tuesday stressed that no one should start popping the pills. "Potassium iodide tablets are not recommended at this time, and can present a danger to people with allergies to iodine, shellfish, or who have thyroid problems," reads a statement on the California Department of Public Health website.

"There's no need for people to take them at this point," Jay Alan, Communications Director for the California Emergency Management Agency, echoed to Fox News Wednesday. "The NRC and the EPA have told us there is no radiation threat on the West coast at this time. They don't anticipate one."

Potassium iodide saturates the thyroid and prevents it from absorbing radioactive iodine, though it does not guard other organs of the body from radiation poisoning. Demand for the drug has spiked so sharply that both F.D.A-approved U.S. manufacturers are scrambling to maintain their supply.

Alan Morris, president of Anbex, Inc., said the drug company was so flooded with phone calls following the tsunami Friday that they ran out of stock by Saturday. "We are completely out of tablets," Morris told Fox News, adding that he expects more pills to be available in one to two weeks. "We are manufacturing them as we speak."

Missouri-based Fleming Pharmaceuticals, which manufactures the drug in liquid form, said it is stepping up production to keep up with demand for the drug. "By the end of this week, we'll ship out everything we have," says company president Phill Dritsas. "We're getting requests from the public, almost everyone...We get calls from pediatricians, from parents, from governments, some of which is relief for Japan."

"I would send a message out in terms of American citizens, that I've not read any reason for people to panic about anything," he says. "But I think it is important. This is a protective measure, and I understand that. So we're trying to prioritize. The greatest need is Japan."

A 2002 federal law requires that state and local governments keep potassium iodide in stock for citizens living within 20 miles of a nuclear power plant, and Dritsas says that since the tsunami, interest from U.S. states is "heightened." Of the 4.8 million units the federal government originally ordered, he says, approximately 1.7 million have expired this year, and another 2.6 million will expire by the end of March. He could not say which states have expressed interest in replenishing their stockpiles.

As for what happens if radiation defies predictions and reaches the California coast, the California Emergency Management Agency says it is prepared. "Those stockpiles are there," Alan says of the government's store of potassium iodide. "We have not only stockpiled in the counties where we have the nuclear power plants both in San Luis Obispo and Orange County, but the emergency [agencies] have those contingencies planned."