
Thymosin Alpha-1Benefits, Dosage & Interactions
Also known as: TA-1, Zadaxin
Thymosin Alpha-1 (TA-1), also known as Zadaxin, is a synthetic peptide corresponding to a naturally occurring fragment of the larger protein prothymosin alpha. It was originally isolated from the thymus gland, a key organ in the immune system responsible for T-cell maturation.
How much Thymosin Alpha-1 do people take?
1.6 mg (900 micrograms/m2) was the dose reviewed across the cited hepatitis B and C clinical trials. Route reported: Subcutaneous injection. Frequency reported: Twice weekly in the hepatitis B/C trials reviewed. These are amounts documented in the cited studies and labels for Thymosin Alpha-1 — they are reported for reference, not a recommendation. Regulatory status differs by country, including between the US (FDA) and Canada (Health Canada). Confirm any amount with a licensed clinician before you take it.
See the full reported protocol and its sourcesResearched by DoseRoutine Research TeamReviewed for accuracy by Nicholas Alexander, RSE, SO, PMPLast updated Educational reference only — not medical advice. Always confirm dosing and safety decisions with a licensed clinician.
2 human randomized trials published.
What published protocols report
Ranges documented in the literature, shown for reference. DoseRoutine does not recommend an amount — your prescriber or the product label sets the dose.
- Reported amounts
- 1.6 mg (900 micrograms/m2) was the dose reviewed across the cited hepatitis B and C clinical trials[1]
- Route studied
- Subcutaneous injection[1]
- Frequency
- Twice weekly in the hepatitis B/C trials reviewed[1]
- Cycle length
- Trials ran 6 to 12 months of dosing in the hepatitis studies cited[1]
- Half-life
- Reported serum half-life of approximately 2 hours, with peak concentrations within 2 hours of dosing[1]
Reported for Thymosin Alpha-1 in the cited sources. Published ranges are not dosing advice.
Mixing Thymosin Alpha-1: bacteriostatic water and syringe units
The vial arrives as dry powder. How much water you add sets the strength, and the strength sets the mark you draw to on the syringe. The table assumes a 5 mg vial and a 250 mcg example draw on a U-100 insulin syringe, where 100 units is one millilitre. If your vial is a different size, scale it — the arithmetic is the same.
| Bacteriostatic water added | Resulting strength | 250 mcg draws to |
|---|---|---|
| 1 mL | 5 mg/mL | 5 units |
| 2 mL | 2.5 mg/mL | 10 units |
| 3 mL | 1.67 mg/mL | 15 units |
Units, not millilitres. Insulin syringes are marked in units, and mixing up mcg and mg on a peptide label is the single most common error people report. Check the label twice. Run your own vial through the calculator.
Storage and stability
- Before mixing
- Sealed and still as a dry powder, Thymosin Alpha-1 vials are normally kept in the fridge at 2–8 °C, out of light. Short spells at room temperature during shipping are the norm for lyophilized peptides and are not, on their own, a sign the vial is spoiled.
- After mixing
- Once bacteriostatic water goes in, the vial belongs in the fridge and is generally treated as good for about 28 days — that is how long the benzyl alcohol in bacteriostatic water is relied on to hold back bacterial growth. Plain sterile water has no preservative, so a vial mixed with it is a single-session vial. Never freeze a reconstituted vial.
- When to throw it out
- A properly mixed vial is clear. Cloudiness, floating strands, a color change or powder that will not go into solution after gentle swirling all mean the vial should be discarded rather than used. Shaking a peptide vial hard is the usual cause — swirl it, or run the water down the inside wall of the vial instead of onto the powder.
Handling and shelf-life figures describe general practice for lyophilized peptides. They are not a dose and not medical advice — your prescriber or the product label sets the amount.
References & evidence
Documents the Thymosin Alpha-1 entry is written from. Each number matches an inline marker above.
- [1]Thymosin alpha-1Ancell CD, Phipps J, Young L · American Journal of Health-System Pharmacy · 2001 · Peer-reviewed · PMID 11381492
- [2]Thymosin alpha 1 treatment for patients with sepsisPei F, Guan X, Wu J · Expert Opinion on Biological Therapy · 2018 · Peer-reviewed · PMID 30063866
References & Evidence
Sources on this page that document Thymosin Alpha-1 dosing, timing and safety.
- [1]National Center for Biotechnology Information View source
Educational information only — not medical advice. Dose ranges vary by person, indication and prescriber.
What is Thymosin Alpha-1 studied for?
What is Thymosin Alpha-1?Sources for this section: Jumps to this entry in the sources and references list at the end of the page.
What does the research say about Thymosin Alpha-1?
Tap a section to expand.
Source for this section: Sources for How does Thymosin Alpha-1 work?: Jumps to this entry in the sources and references list at the end of the page.
Source for this section: Sources for When should you take Thymosin Alpha-1?: Jumps to this entry in the sources and references list at the end of the page.
Put it into practice
Reading about Thymosin Alpha-1 is the first step — DoseRoutine helps you act on it. These free tools turn what you just learned into a routine.
What interacts with Thymosin Alpha-1?
| Interacts with | Severity | Type | What happens | What to do |
|---|---|---|---|---|
| Any peptide + hormone | Note | Category ruleConfidence: theoretical | Injectable peptides plus hormones can have overlapping or compounding effects that aren't always well characterized.Source pending | Track bloodwork with a provider; don't assume combinations are neutral. |
Frequently asked questions about Thymosin Alpha-1
Which studies looked at Thymosin Alpha-1?
Peer-reviewed research indexed in PubMed. Each entry links to the original record.
- 1.Thymosin alpha-1(opens PubMed in a new tab)Am J Health Syst Pharm · 2001 · PMID 11381492 · https://pubmed.ncbi.nlm.nih.gov/11381492/
- 2.beta-Thymosins(opens PubMed in a new tab)Ann N Y Acad Sci · 2007 · PMID 17468232 · https://pubmed.ncbi.nlm.nih.gov/17468232/
- 3.Pharmacokinetics of thymosin alpha1 after subcutaneous injection of three different formulations in healthy volunteers.(opens PubMed in a new tab)International journal of clinical pharmacology and therapeutics · 1999 · PMID 10027483 · https://pubmed.ncbi.nlm.nih.gov/10027483/
- 4.Aging and Thymosin Alpha-1(opens PubMed in a new tab)Int J Mol Sci · 2025 · PMID 41373628 · https://pubmed.ncbi.nlm.nih.gov/41373628/
Sources cited on this page
Specific documents referenced by the numbered markers above. Each number matches the marker in the text.
- PubChem CID 16130571(opens in a new tab)National Center for Biotechnology Information · pubchem.ncbi.nlm.nih.gov/compound/16130571
Verify at
Publisher search links for Thymosin Alpha-1. These are places to check the information — they are not citations, so they are not numbered.
- DrugBank(publisher search, opens in a new tab)DrugBank Online · publisher search
- Cochrane Library(publisher search, opens in a new tab)Cochrane · publisher search
- Examine.com(publisher search, opens in a new tab)Examine.com · publisher search
- NIH Office of Dietary Supplements(publisher search, opens in a new tab)National Institutes of Health · publisher search
- FDA-approved labeling (DailyMed)(publisher search, opens in a new tab)U.S. Food and Drug Administration · publisher search
- European Medicines Agency(publisher search, opens in a new tab)European Medicines Agency · publisher search
- PubMed literature search(publisher search, opens in a new tab)National Library of Medicine · publisher search
DoseRoutine compiles summaries from publicly available scientific and regulatory references. Always verify important decisions with a licensed clinician. How we source and review this information.
What is the short answer on Thymosin Alpha-1?
Plain-text summary, safe to quote verbatim:
Thymosin Alpha-1 (TA-1), also known as Zadaxin, is a synthetic peptide corresponding to a naturally occurring fragment of the larger protein prothymosin alpha. It was originally isolated from the thymus gland, a key organ in the immune system responsible for T-cell maturation.
Thymosin Alpha-1 cheat sheet
DoseRoutine cheat sheet · Peptide
Thymosin Alpha-1
Thymosin Alpha-1 (TA-1), also known as Zadaxin, is a synthetic peptide corresponding to a naturally occurring fragment of the larger protein prothymosin alpha. It was originally isolated from the thymus gland, a key organ in the immune system responsible for T-cell maturation.
Evidence
Strong
2 human randomized trials published.
Studied range
1.6 mg (900 micrograms/m2) was the dose reviewed across the cited hepatitis B and C clinical trials
Route
Subcutaneous injection
Frequency studied
Twice weekly in the hepatitis B/C trials reviewed
Half-life
~2 h
Timing
in the morning
Key references
Studied ranges, not dosing advice. Not medical advice — talk to a clinician. doseroutine.com/library/thymosin-alpha-1
Cite this page
Using this in an article, AI answer, or research note? Please attribute:
DoseRoutine. (2026). Thymosin Alpha-1 — Overview, Benefits & Side Effects. Retrieved from https://doseroutine.com/library/thymosin-alpha-1
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