Thymosin Alpha-1 Dosing Calculator
Thymosin Alpha-1: Immunomodulator approved in 35+ countries.
Pre-filled with the most-reported community reconstitution protocol for Thymosin Alpha-1. See how 1 mL and 2 mL of bacteriostatic water change concentration and syringe-draw volume, then adjust the calculator below for your own vial.
Quick answer · Community-reported standard
A 5 mg vial of Thymosin Alpha-1 reconstituted with 2 mL of bacteriostatic water yields a concentration of 2.50 mg/mL. At that concentration, a 1.5 mg dose of Thymosin Alpha-1 equals 60 units on a U-100 insulin syringe (0.600 mL). Thymosin Alpha-1 is typically administered twice weekly via subcutaneous.
Thymosin Alpha-1 reconstitution: 1 mL vs 2 mL bac water
Bacteriostatic water volume is flexible. Less water means higher concentration and smaller injection volumes; more water means lower concentration and easier dose precision. Both options below are valid for a 5 mg vial.
| BAC water added | Concentration | Volume per 1.5 mg dose | Draw on U-100 syringe (units) |
|---|---|---|---|
| 1 mL | 5.00 mg/mL | 0.300 mL | 30 units |
| 2 mL | 2.50 mg/mL | 0.600 mL | 60 units |
Calculate your Thymosin Alpha-1 dose
Alternative Thymosin Alpha-1 protocols
Beyond the default above, Thymosin Alpha-1 is also reported in the following protocols. Use these as starting points and recalculate with the tool above.
Daily Low-Dose Protocol
Community- Dose
- 300-500 mcg
- Frequency
- Once daily
- Duration
- 4-8 weeks
- Route
- Subcutaneous
Community-adapted daily dosing for gradual immune modulation; easier measuring with standard vials
Acute Immune Challenge Protocol
Community- Dose
- 1.6 mg
- Frequency
- Daily for 3-5 days then twice weekly
- Duration
- 2-4 weeks
- Route
- Subcutaneous
Used during acute infections or illness onset; front-loading approach before switching to maintenance
Long-Term Maintenance Protocol
Community- Dose
- 1.5 mg
- Frequency
- Once weekly
- Duration
- Ongoing (3 months on, 1 month off)
- Route
- Subcutaneous
Used by immunocompromised individuals for ongoing immune support with periodic breaks
Chronic Hepatitis B Treatment
Clinical- Dose
- 1.6 mg subcutaneous injection
- Frequency
- Twice weekly (separated by 3-4 days)
- Duration
- 6 to 12 months
This is the standard approved regimen for Zadaxin in countries where it is registered for hepatitis B treatment. Response assessment typically occurs at 6 months with potential extension to 12 months. Sustained virological response continues to improve after treatment cessation due to the immune-mediated mechanism.
General Immune Support
Clinical- Dose
- 1.6 mg subcutaneous injection
- Frequency
- Twice weekly
- Duration
- Variable, typically 3-6 months
Used in clinical settings for immune reconstitution in immunocompromised patients, including those with chronic infections or age-related immunosenescence. Duration is guided by clinical response and immune biomarker monitoring (CD4/CD8 ratios, NK cell counts).
Thymosin Alpha-1 reconstitution & storage
Zadaxin is supplied as a sterile lyophilized powder (1.6 mg per vial) with accompanying diluent (1 mL sterile water for injection). Reconstitute by injecting the full volume of diluent into the vial, then gently swirl (do not shake) until the powder is completely dissolved. The reconstituted solution should be clear and colorless. Use immediately after reconstitution; do not store reconstituted solution.
Store lyophilized vials at 2-8 degrees Celsius (36-46 degrees Fahrenheit), protected from light. Do not freeze. Unopened vials are stable for 24 months under recommended storage conditions. Reconstituted solution should be used immediately and any unused portion discarded. Do not use if the reconstituted solution appears discolored or contains particulate matter.
Thymosin Alpha-1 dosing FAQ
How much bacteriostatic water should I add to a 5 mg vial of Thymosin Alpha-1?
The community standard is 2 mL of bacteriostatic water for a 5 mg Thymosin Alpha-1 vial. That gives a concentration of 2.50 mg/mL, so a 1.5 mg dose is 60 units on a U-100 insulin syringe. Adding 1 mL instead doubles the concentration to 5.00 mg/mL and halves the draw to 30 units. Less water = smaller injection volume but harder to measure precisely.
How many syringe units is a 1.5 mg dose of Thymosin Alpha-1?
On a standard U-100 insulin syringe, a 1.5 mg dose of Thymosin Alpha-1 is 60 units when the 5 mg vial is reconstituted with 2 mL of bacteriostatic water (2.50 mg/mL). If you use 1 mL of bac water instead, draw 30 units (5.00 mg/mL).
What is the standard Thymosin Alpha-1 dose?
Community-reported protocols for Thymosin Alpha-1 typically use 1.5 mg twice weekly via Subcutaneous. 1.5 mg is a common starting dose. Most commonly cited clinical-derived protocol; matches Zadaxin prescribing in many countries
How long does a vial of Thymosin Alpha-1 last at 1.5 mg twice weekly?
A 5 mg vial of Thymosin Alpha-1 contains roughly 3 doses at 1.5 mg per injection. At twice weekly dosing, that is approximately 11 days (about 2 weeks) of supply per vial. Reconstituted Thymosin Alpha-1 should generally be used within 28 days when refrigerated.
Where do you inject Thymosin Alpha-1?
Thymosin Alpha-1 is typically administered subcutaneous. Common subcutaneous sites are the lower abdomen (at least an inch from the navel), the outer thigh, and the love handles. Rotate sites with each injection to reduce localized irritation and bruising.
Can I use sterile water instead of bacteriostatic water for Thymosin Alpha-1?
Bacteriostatic water (containing 0.9% benzyl alcohol as a preservative) is strongly preferred for multi-dose vials like Thymosin Alpha-1 because it inhibits microbial growth and lets a single vial be used over multiple weeks. Sterile water has no preservative and should generally be reserved for single-use preparations only.
More on Thymosin Alpha-1
Thymosin Alpha-1 overview
Mechanism of action, primary uses, and research summary
Thymosin Alpha-1 dosing protocols
Full clinical and research-based dosing reference
Thymosin Alpha-1 community protocols
Real-world usage patterns from peptide communities
Thymosin Alpha-1 side effects
Reported adverse effects and safety considerations
Medical Disclaimer
This website is for educational and informational purposes only. The information provided is not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before using any peptide or supplement.