Hyperthyroidism treatment in cats usually involves antithyroid medication or the use of radioactive iodine to destroy the abnormal (overactive) tissue growing in the thyroid gland. surgery to remove the abnormal tissue is generally not advised, as the surgery could also accidentally destroy parathyroid tissue. the parathyroid gland releases a hormone called pth that increases blood calcium levels. based on your knowledge of homeostasis, predict why surgery is ill-advised.