clinical conditions requiring adjustment of thyroxine dose

Last reviewed 01/2018

Conditions in which an increased dose of thyroxine may be required:

  • increased thyroxine clearance:
    • phenytoin
    • carbamazepine
    • rifampicin

  • reduced intestinal absorption
    • ferrous sulphate
    • cholestyramine
    • aluminium hydroxide

  • increased concentration of serum thyroxine binding globulin:
    • pregnancy
    • increased body mass (1)

  • reduced thyroxine clearance:
    • aging

Reference:

  • Wood J. (1994).Thyroxine therapy. NEJM, 331 (3), 174-80.