Index/Thymulin

THYMULIN

FTS · Serum Thymic Factor · Glu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-OH

Thymic hormone — T-cell maturation and immune aging.

FDA

Research Only

WADA

Not Listed

HALF-LIFE

Unknown

ROUTE

SubQ injection

SCHEDULE

Daily or 3× weekly

In Plain English

Thymic hormone — T-cell maturation and immune aging.

Status & Legality

What do these mean?

NATTY?

No Test Exists

No established test exists for this compound.

FDA

Research Only

For research purposes only. Not FDA approved.

WADA

Not Listed

Not currently on WADA prohibited list.

COMPOUNDING

Not from pharmacies

Not available from licensed compounding pharmacies.

PRESCRIBED

Not prescribed

Not prescribed in conventional medicine.

ROUTE

SubQ injection

Administration via subq injection.

Who It's For

T-cell maturation

Immune aging

Thymus support

Anti-inflammatory

How It Works

Thymulin is the primary zinc-dependent thymic hormone responsible for T-cell differentiation and maturation. Levels decline sharply after age 60, paralleling immune senescence. Research shows supplementation restores NK cell activity, reduces pro-inflammatory cytokines, and improves immune surveillance in aging models.

Side Effects

Mild injection site reactions

Transient immune activation symptoms

Generally well tolerated

Common Mistakes

•

Not ensuring adequate zinc status before starting — Thymulin is zinc-dependent; deficiency renders it effectively inactive

•

Using oral preparations instead of SubQ injection — Thymulin is not bioavailable orally

•

Skipping zinc co-supplementation — zinc is structurally required for thymulin activity; always supplement 25 mg zinc alongside

Drug & Supplement Interactions

Zinc supplements — required cofactor; optimize zinc status to baseline (25–50 mg/day) before and during Thymulin use

Immunosuppressants — direct antagonism; avoid in transplant patients

Corticosteroids — reduce thymic output and may blunt Thymulin's T-cell maturation effects

The PepVault Take

Thymulin's zinc-dependency is what most users miss — and it's not optional. Before starting, test zinc levels and correct any deficiency. The triple immune protocol (Thymulin + Thymosin Alpha-1 + Thymalin) addresses thymic function from three distinct angles and represents the most comprehensive immune restoration approach in the index.