potassium iodide only works for cesium, it prevents leukemia from thyroid cancer by saturating your thyroid with iodide so cesium charged iodide cant saturate your thyroid. it does not protect against other radioactive isotopes, if the nuclear fallout contains barium, polonium, plutonium, uranium, strontium etc etc. then you will be in for just as deadly of an experience. you need first line of defence, respiratory protection from a gasmask filter that is classed for n (nuclear), you could find nbc filters, nuclear biological, chemical and they will work best to prevent ingestion of radioactive isotopes. remember, iodide (not iodine) only protects against cesium that was majority of chernobyl's leak. its not a save all solution. source: im a chemist, i make these types of medicines, i research isotopes and do lab work. best remedy to nuclear war is to not have nuclear war.
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