Sodium iodide is a chemical compound made up of sodium and iodine, represented by the formula NaI. It appears as a white, crystalline solid and is highly soluble in water. Sodium iodide is commonly used in various applications, including as a dietary supplement to prevent iodine deficiency and in medical imaging procedures. In the field of medicine, sodium iodide is often used in nuclear medicine for diagnostic imaging of the thyroid gland. It can also be utilized in the treatment of certain thyroid conditions, such as hyperthyroidism. Additionally, sodium iodide plays a role in radiopharmaceuticals for targeted radiation therapy.