Orals

T4

Name: T4
Brand: Quanta Pharmaceuticals

Levothyroxine, the storage thyroid prohormone studied for sustained metabolic and weight-management support.

T4 (Levothyroxine) is the principal storage form of thyroid hormone, studied for its role in providing sustained thyroid activity through peripheral conversion to the active T3 form. This formulation supplies 50 tablets of 100mcg per tub. Chemically classified as C15H11I4N, Levothyroxine is roughly 99% bound to plasma proteins and converted to Liothyronine (T3) by deiodinase enzymes in peripheral tissues as required. This conversion step provides a buffered, longer-acting source of thyroid hormone activity compared with direct T3 administration. T4's elimination half-life runs about 6-7 days in euthyroid research subjects, stretching to 9-10 days in a hypothyroid state and shortening to 3-4 days in a hyperthyroid one — a pharmacokinetic property that has made it a frequent point of comparison against faster-acting T3 in metabolic research.

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Specifications

Tablets

Dose Per Tablet

100mcg

Half-Life

7 days

Administration

Oral

Chemical Structure

C15H11I4N

Research Benefits

Sustained Thyroid Support — A long half-life is studied for providing stable, buffered thyroid hormone activity.
Peripheral T3 Conversion — Research examines how deiodinase enzymes convert T4 to the active T3 form as tissues require it.
Metabolic Rate Research — Investigated for its downstream role in maintaining basal metabolic rate.
Weight-Management Support — Frequently studied alongside caloric-deficit protocols for its metabolic contribution.
Infrequent Dosing — A seven-day half-life allows for stable levels with less frequent dosing than active T3.

How It Works

Levothyroxine is the prohormone form of thyroid hormone, circulating in the bloodstream largely bound to carrier proteins. Peripheral tissues convert it into the active Liothyronine (T3) via deiodinase enzymes, releasing active hormone according to local tissue demand.

This conversion-dependent mechanism provides a buffered, self-regulating supply of thyroid activity, distinct from the more immediate action of directly administered T3. Its seven-day half-life allows research protocols to maintain stable circulating hormone levels with comparatively infrequent dosing.

⚠ For Research Use Only

This product is supplied strictly for in-vitro laboratory and preclinical research use. It is not a drug, food, dietary supplement, or cosmetic, and is not intended for human or animal consumption, diagnosis, treatment, or prevention of any disease. T4 must be handled only by qualified individuals trained in proper laboratory safety procedures.

By purchasing, the buyer confirms this product is being acquired for legitimate research purposes and assumes full responsibility for its handling, storage, and use in compliance with all applicable local, national, and international laws.