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Immune & Anti-Inflammatory

Thymulin

FTS · facteur thymique sérique · zinc-thymulin
researchnichesubQ injection

What it is

Thymulin is a nine-amino-acid peptide hormone produced by thymic epithelial cells. Active only when bound to zinc — without zinc, no biological activity. Levels decline with age. Studied for immune support in older adults and immune-compromised patients.

How it works

Promotes T-cell maturation in the thymus, particularly the conversion from immature thymocytes to functional T-cells. Adequate dietary zinc is essential for thymulin function. Some anti-inflammatory and analgesic effects via opioid pathways.

Benefits

Timeline

Week 1–2
Subtle immune effects.
Week 4–8
Cumulative T-cell normalization.

Dosing & titration

Standard dose200–500 mcg subQ, 2–3x weekly
Cycle length8–12 weeks
When to titrate upLimited human dose-response data; ensure adequate dietary zinc.

Side effects & risks

Requires adequate zinc. Pair with dietary zinc (15–30 mg/day) for activity.

Typical price

$80–$150/moLimited availability.

Studies

Educational reference only. Not medical advice.