Final answer:
Administering non-radioactive iodine before radioactive iodide helps to protect the thyroid gland by preventing excessive absorption of radioactivity, thereby reducing the risk of radiation damage during diagnostic procedures or treatments for thyroid-related conditions.
Step-by-step explanation:
If a clinician administers Lugol's solution or potassium iodide prior to giving radioactive iodide, this is usually done as a protective measure for the thyroid gland. These non-radioactive forms of iodine saturate the thyroid and prevent the uptake of radioactive iodide, which can be harmful if absorbed in large quantities. Therefore, when non-radioactive iodine is administered before a diagnostic procedure with I-131, it helps ensure that the thyroid doesn't absorb too much radioactivity, reducing the risk of radiation damage to the thyroid cells. This is particularly important during the treatment of conditions such as hyperthyroidism or thyroid cancer, where the goal is to use radioactive iodine to ablate overactive thyroid tissue or cancerous cells without harming the rest of the organ.