Used in medicine for the treatment of thyroid disorders, particularly in cases of iodine deficiency. It serves as a source of iodine to support normal thyroid function and hormone production. Also employed in radiation protection, where it helps block the uptake of radioactive iodine by the thyroid gland during nuclear emergencies. In diagnostic procedures, it is used in radioactive form (I-131 or I-123) for imaging the thyroid and detecting abnormalities. In industrial settings, it acts as a catalyst in organic synthesis and is used in the production of certain dyes and pharmaceuticals. Additionally, sodium iodide is utilized in scintillation detectors for measuring radiation due to its ability to emit light when exposed to ionizing radiation.