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T3 (Triiodothyronine)

National Institute of Mental Health (NIMH) · FDA-approved active Small molecule

T3 (triiodothyronine) is a thyroid hormone that binds to thyroid hormone receptors in cells to increase metabolic rate and cellular energy production.

T3 (triiodothyronine) is a thyroid hormone that binds to thyroid hormone receptors in cells to increase metabolic rate and cellular energy production. Used for Adjunctive treatment for major depressive disorder (investigational), Hypothyroidism (established therapeutic use).

At a glance

Generic nameT3 (Triiodothyronine)
SponsorNational Institute of Mental Health (NIMH)
Drug classThyroid hormone
TargetThyroid hormone receptor (TR-alpha, TR-beta)
ModalitySmall molecule
Therapeutic areaPsychiatry / Endocrinology
PhaseFDA-approved

Mechanism of action

T3 is the active form of thyroid hormone that enters cells and binds to thyroid hormone receptors (TR-alpha and TR-beta), which act as nuclear transcription factors. This binding increases the expression of genes involved in oxidative metabolism, thermogenesis, and cellular respiration. T3 has been studied as an adjunctive treatment in mood disorders, particularly depression, based on evidence that thyroid dysfunction is associated with psychiatric symptoms.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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