Oral T3 may be compounded in either immediate-release or sustained-release formulations. T3 acts in a manner comparable to the naturally occurring thyroid hormone triiodothyronine. It is supplied as an oral capsule and is intended for use as replacement or adjunctive therapy in the management of hypothyroidism.
The human body contains two primary thyroid hormones: triiodothyronine (T3) and thyroxine (T4). Triiodothyronine is the more biologically active hormone. In the body, T4 is converted into T3. Additionally, T3 has a faster onset of action than T4 and may be used in individuals who do not efficiently convert T4 to T3.
T3 is indicated for the following:
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Hypothyroidism: As replacement therapy in primary (thyroidal), secondary (pituitary), or tertiary (hypothalamic) congenital or acquired hypothyroidism
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Pituitary Thyrotropin (Thyroid-Stimulating Hormone, TSH) Suppression: As an adjunct to surgery and radioiodine therapy in the management of well-differentiated thyroid cancer
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Thyroid Suppression Test: As a diagnostic agent in suppression testing to distinguish suspected mild hyperthyroidism or thyroid gland autonomy
