Thymosin Alpha-1
1.5 mg · 2×/week
Robert
Founder, F*CK Getting Old — independent researcher, not a medical professional.
Last reviewed · 2 cited sources
Evidence
- Human Studies
- 25
- Animal Studies
- 30
- Clinical Status
- Off-label
- Confidence
- Moderate
- Long-Term Safety
- Established in the countries where it is an approved drug; not FDA approved in the US
What this score is: a measure of how much research exists and how far along it is (animal-only vs. human trials, research-stage vs. FDA approved) — not how safe, effective, or worth trying a compound is. A low score usually means “early stage” or “understudied,” not “bad.” A high score doesn’t mean “better” for your goals than a lower-scored one.
This is not my personal rating of the compound, not a recommendation, and not medical advice. It’s a general research synthesis for informational purposes only, not a live literature count. See the linked research and talk to a licensed clinician before making decisions based on it.
Mechanism
A naturally occurring thymic peptide that modulates T-cell function and immune response. Marketed outside the US as Zadaxin for chronic hepatitis B/C and as a cancer/immune adjuvant, and studied in various infectious-disease and immune-modulation trials — not FDA approved in the US.
Common Protocols
- 1.5 mg twice weekly, subcutaneous, per typical immune-support protocols
Side Effects
- Injection site reaction
- Generally well-tolerated in trials for its approved (non-US) indications
Interactions
- Immunomodulatory — caution combining with other immune-affecting drugs, or in autoimmune conditions
Practical Details
- Cost
- $$
- Typical Vial Size
- 10 mg
- Storage
- Refrigerate after reconstitution
Key Studies & Reviews
- Dominari A et al. (2020). Thymosin alpha 1: a comprehensive review of the literature. World J Virol. PMID 33362999.
- Simonova MA et al. (2025). Aging and thymosin alpha-1. Int J Mol Sci. PMID 41373628.
Search the Research
Thymosin Alpha-1 FAQ
What is the typical Thymosin Alpha-1 dosage?
Commonly reported protocols: 1.5 mg twice weekly, subcutaneous, per typical immune-support protocols. Our reference entry uses 1.5 mg, 2×/week. These reflect protocols reported in research and user communities, not a medical recommendation — dosing should be decided with a clinician.
What are the side effects of Thymosin Alpha-1?
Reported side effects include: Injection site reaction; Generally well-tolerated in trials for its approved (non-US) indications.
Is Thymosin Alpha-1 FDA approved?
Thymosin Alpha-1 is not FDA approved for the uses discussed here; it is used off-label or through compounding pharmacies, with less oversight of quality and dosing.
How much research is there on Thymosin Alpha-1?
Our evidence profile counts roughly 25 human and 30 animal studies, with moderate overall confidence. Long-term safety: Established in the countries where it is an approved drug; not FDA approved in the US.
Does Thymosin Alpha-1 interact with other drugs or supplements?
Immunomodulatory — caution combining with other immune-affecting drugs, or in autoimmune conditions.
How do I reconstitute Thymosin Alpha-1?
A common setup is a 10 mg vial mixed with 2 mL of bacteriostatic water, which puts a 1.5 mg dose at about 15 units on a U-100 insulin syringe. Use the reconstitution calculator with your own vial and dose to get exact numbers. Storage: Refrigerate after reconstitution.
Related compounds
Immune modulation