Key Points
Î Levothyroxine should remain the standard of care for treating
hypothyroidism.
Î There is no consistently strong evidence for the superiority of
alternative preparations (e.g., levothyroxine–liothyronine combination
therapy or thyroid extract therapy) over monotherapy with
levothyroxine in improving health outcomes.
Î For patients who feel unwell while taking levothyroxine therapy
there is currently insufficient evidence to support the routine use of
combination therapy due to uncertainty about the long-term risk-
benefit ratio.
Î Future research needs include the development of superior
biomarkers of euthyroidism to supplement the use of serum TSH
measurements and long term trials testing the health outcomes of
combination therapy or thyroid extract therapy.
