Thyrotoxic myopathy the use of radioactive iodine which directly destroys the overactive thyroid gland. The thyroid gland naturally uses iodine to produce thyroxine and other hormones. It cannot distinguish between normal iodine and the radioactive version. Administering the radioactive isotope causes the thyroid to take in the lethal iodine and quickly radiation destroys it. Typically overproduction of thyroxine using radio-iodine is blocked with one dose. The drawback to this treatment is the thyroid gland is completely destroyed and patients often develop hypothyroidism. Some do so only a few months after treatment while others may not be affected for 20–30 years. Hypothyroidism patients
Iodine and iodate anions are often used for quantitative volumetric analysis, for example in iodometry and the iodine clock reaction (in which iodine also serves as a test for starch, forming a dark blue complex), and aqueous alkaline iodine solution is used in the iodoform test for methyl ketones. The iodine test for starch is still used to detect counterfeit banknotes printed on starch-containing paper. The spectra of the iodine molecule, I, consists of (not exclusively) tens of thousands of sharp spectral lines in the wavelength range 500-700 nm. It is therefore a commonly used wavelength reference (secondary standard). By measuring