Compounds / Hormonal / T4 (Levothyroxine)

T4 (Levothyroxine)

T4 — Levothyroxine (Thyroxine — Thyroid Prohormone)
HormonalFDA: FDA-APPROVED (hypothyroidism —...WADA: PROHIBITED — Category S4...

Overview

FDA-approved hypothyroidism treatment. Most prescribed drug globally. Research: thyroid optimization in aging, metabolic syndrome, cognitive function. T4 monotherapy vs T4+T3 combination ongoing debate.

Mechanism of Action

Thyroid prohormone converted peripherally (liver, kidney, muscle) to active T3 via deiodinase enzymes. 7-day half-life enables once-daily dosing. Regulates metabolism, growth, development via nuclear thyroid hormone receptors. Most commonly prescribed medication worldwide.

Molecular Profile

Molecular weight
776.9 Da
CAS number
51-48-9

Key Research Findings

Thyroid prohormone; 7-day half-life; peripheral T3 conversion; FDA-approved; most prescribed drug globally; metabolic regulation.

Published Research

Thyroid (2012)
Garber JR et al. Clinical Practice Guidelines for Hypothyroidism — ATA/AACE
View source

Related Hormonal Compounds

HCGGonadorelinKisspeptinOxytocinHMGACTH 1-39
Clinical Guidance

Research data is not a treatment plan. If you are considering T4 (Levothyroxine), the questions that matter are whether it suits your history, your labs and your goals. That is a conversation with a licensed physician, not a lookup.

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