L-thyroxine monotherapy is still considered the standard of care

Patients with elevated TSH values should be evaluated for possible hypothyroidism, taking into account the respective reference standard value ranges and intra- and interindividual variability. In patients with hypothyroidism requiring treatment, current guidelines advocate the use of levothyroxine as the agent of choice. In clinical trials, the majority did not show superiority of combination therapy of T3 and T4 over L-thyroxine monotherapy.