Euthyrox® (levothyroxine sodium) is a synthetic thyroid hormone and the standard treatment for hypothyroidism. It is also used for treatment of euthyroid goiter and suppressive therapy of differentiated thyroid cancer.

Merck Serono is a world leader in the treatment of hypothyroidism. Euthyrox® has been on the market since 1973 and is the major brand of the division’s thyroid treatment franchise, which also includes the brands Eutirox and Levothyrox.

The synthetically produced thyroid hormone levothyroxine (LT4) is identical to the natural T4 hormone. It replaces what the body cannot produce on its own.

In order to treat each patient according to individual needs, tablets are available in 12 different dosage strengths with a levothyroxine sodium content ranging from 25 to 200 µg. Patients usually need to take only one tablet per day.

The individual daily dose should be determined on the basis of laboratory tests and clinical examinations.

Levothyroxine can be given alone as monotherapy; in certain cases, levothyroxine is administered in combination with a small amount of triiodothyronine (T3) in order to achieve optimum metabolic control.