Examples
Mechansims
Inhibition of Ionic Trapping
  • Thiocyanate
  • Perchlorate
  • Inhibition of the sodium-iodide symporter (NIS) on the thyroid follicular cell membrane.
Inhibition of Hormone Synthesis
  • Thionamides:
    • Propylthiouracil
    • Carbimazole
    • Methimazole
  • Inhibition of thyroperixodase preventing organification or iodine
Inhibition of Hormone Release
  • Iodides:
    • Potassium Iodide (Lugol's Iodine)
    • Sodium Iodide
  • Increased resistance of thyroglobulin to proteolytic degradation
  • (Iodides also prevent ionic trapping and hormone synthesis)
Prevention of Peripheral Conversion to Thyroid Hormone
  • Corticosteroids
  • Propranolol
  • Propylthiouracil
  • Amiodarone
  • Radiocontrast media
  • Increased type 3 deiodinase activity
Destruction of Thyroid Tissue
  • Radioactive iodine (131,125,123)