Thymulin
Thymulin (also known as Facteur Thymique Sérique/FTS) is a nonapeptide hormone produced exclusively by the thymus gland. It requires zinc to be biologically active and plays a critical role in T-cell differentiation and maturation. Thymulin levels decline dramatically with age as the thymus involutes, contributing to immunosenescence. Supplemental thymulin restores immune balance, reduces chronic low-grade inflammation, and has shown neuroprotective effects. It is being studied for autoimmune conditions, aging immunity, and neurodegenerative diseases.
Frequency
2-3x per week
Cycle Length
4-8 weeks on, 4 weeks off
Route
Subcutaneous
Research Level
Emerging
Goals
Dosing Protocol
1-5 mg subcutaneously. Dosing varies by protocol. With standard reconstitution (20 mg in 2 mL), 1 mg = 10 units and 5 mg = 50 units on a U-100 insulin syringe.
Reconstitution
Add 2 mL bacteriostatic water to a 20 mg vial.
Timing
Morning.
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Potential Side Effects
- Injection site redness
- Mild fatigue
- Generally well tolerated
Important Warnings
- Requires adequate zinc levels for biological activity
- Use with caution in autoimmune conditions
Works Well With
Research References
- Bach JF. Clin Immunol Immunopathol. 1983;27(1):1-12. doi:10.1016/0090-1229(83)90051-0
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Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Thymulin may be regulated differently in various jurisdictions. Always consult with a qualified healthcare provider before beginning any peptide protocol. PepStack Pro does not sell peptides or provide medical advice. Content reviewed by Dr. Seth Miller, MD.