Levothyroxine
Levothyroxine (Synthroid) is a thyroid hormone replacement used for congenital or acquired hypothyroidism, with the Synthroid and Levothroid tablet formulations listed in this catalogue.

Levothroid
Hypothyroidism
25mcg · 50mcg · 75mcg · 100mcg · 112mcg · 125mcg · 200mcg
Levothyroxine tablets for hypothyroidism and to suppress thyroid-stimulating hormone. They replace the missing thyroid hormone.
Key points
- SYNTHROID has a narrow therapeutic index, so too much or too little treatment can affect several body functions.
- TSH is not a reliable way to judge treatment level in secondary or tertiary hypothyroidism.
- SYNTHROID tablets contain no ingredients derived from wheat, barley or rye.
What Levothyroxine is used for
Levothyroxine sodium supplies T4, a thyroid hormone that the body converts partly to the more active T3. It is listed for Hypothyroidism and may also be used with surgery and radioiodine therapy for Thyroid-stimulating Hormone Suppression in thyrotropin-dependent well-differentiated thyroid cancer.
Further reading
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