Thymulin

What is Thymulin?

Thymulin is a chemically defined hormone your own thymus makes, and the headline fact is that it only works when it is holding onto zinc. It is a nine-amino-acid peptide secreted by thymic epithelial cells, first isolated from pig serum and named facteur thymique serique, or FTS, by the Bach and Dardenne group, who established its sequence the same year, per Dardenne 1977. That is the single biggest thing that sets it apart from the undefined Russian-style thymic extracts and from the extract thymalin. Thymulin is one molecule with a known sequence, a known shape, and a known synthetic route, not a peptide soup.

From the BioHarmony report, reviewed 2026-09-08.

How it is thought to work

Drives T-cell differentiation through specific high-affinity receptors and suppresses inflammatory cytokines

Safety watch-outs

• Pain that worsens with dosing (possible low-dose hyperalgesic direction): stop and reassess the dose.
• Any new or worsening symptom from grey-market material (possible contamination or wrong identity): stop and discard the vial.
• Active or suspected cancer: do not use
• immune and neuroendocrine signaling is not something to experiment with here.
• Pregnancy or breastfeeding: avoid, since there is no human safety data.

Full risk profile in the BioHarmony report.

Dosing as published

No approved-label or study protocol is recorded for Thymulin yet.

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