Science, Tech, Math › Science Radiation Pills Share Flipboard Email Print adventtr/Getty Images Science Chemistry Chemical Laws Basics Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 28, 2020 Radiation pills may be given in the event of nuclear accidents, nuclear attacks, or in the course of certain radioactive medical treatments. Here's a look at what radiation pills are and what is in them. A Description of Radiation Pills Radiation pills are tablets of potassium iodide, a common salt. Potassium iodide is a source of dietary iodine. The way radiation pills work is by saturating the thyroid with stable iodine so that radioactive iodine isotopes aren't needed and thus aren't absorbed by the body. Potassium iodide or KI is effective at protecting the thyroid of developing fetuses, babies, children, and young adults from developing thyroid cancer from exposure to iodine isotopes. A dose of potassium iodide is effective for 24 hours. However, the pills don't protect against any other form of radiation exposure nor do they protect any other organ. They can't reverse the damage that has already occurred. Radiation pills aren't effective for persons over the age of 40 because their thyroid activity doesn't cause them to suffer much of an effect from iodine radioisotope exposure. Radiation Pill Alternatives There are natural alternatives to potassium iodide pills. Sources of dietary iodine block absorption of undesirable radioisotopes of iodine. You can get iodine from iodized salt, sea salt, kelp, and seafood. Is There a General-Purpose Radiation Pill? No, there is no pill that will protect you from radiation exposure. Your best course of action is to remove any contaminated clothing and shower to remove radioactive material. Radiation may be blocked by physically separating yourself from its source by a material known to block that type of radiation. For example, you can block alpha radiation with a sheet of paper. A wall will block alpha radiation. Lead is used to block x-radiation. The energy of the radiation determines what you'll need to use to prevent exposure.