PeptideCalculations
28-amino-acid peptide · 5 mg / 10 mg vials

Thymosin Alpha-1 calculator

Thymosin alpha-1 is thymalfasin, sold as Zadaxin in more than 30 countries (not the US). The labeled dose is 1.6 mg subcutaneous twice a week for 6 to 12 months, the same regimen as the 1998 hepatitis B trial that supports it.

mL
Draw to
—units
— mL on a U-100, 1 mL barrel
Concentration
—mg/mL
— mcg per unit
Doses in the vial
—
of
Thymosin Alpha-1 dosage
1.6 mg twice weeklyper dose · clinical trial (Chien et al. 1998, Hepatology, 98 chronic hepatitis B patients, randomized; same dose as the Zadaxin label, 900 mcg/m2)
Frequency
twice weekly, 3 to 4 days apart
Timing
any time of day
Cycle
label: 6 to 12 months; community: 4 to 12 weeks, repeated as needed
Route
subcutaneous only (the label says never intravenous)
Easy mix
10 mg + 2 mL = 5 mg/mL, so 1.6 mg = 0.32 mL = 32 units. A 5 mg vial + 1 mL gives the same 32 units. The Zadaxin vial is 1.6 mg in 1 mL, one dose per vial.

Full Thymosin Alpha-1 dosage chart →

Thymosin Alpha-1 units chart

10 mg vial. Rows are doses; columns show the units to draw on a U-100 syringe at each water volume.

10 mg vial + 2 mL = 5 mg/mL (5,000 mcg/mL, 50 mcg per unit on U-100)
DosemLU-100 unitsDoses per vial
100 mcg0.022100
200 mcg0.04450
250 mcg0.05540
500 mcg0.11020
1 mg0.22010
2 mg0.4405
2.5 mg0.5504
5 mg11002
10 mg22001

Other mixes: 10 mg + 1 mL · 10 mg + 3 mL · 5 mg + 2 mL

About the Thymosin Alpha-1 math

Thymosin Alpha-1, sometimes abbreviated Tα1, is a 28-amino-acid peptide. Suppliers list it in 5 mg and 10 mg vials of lyophilized powder. The example draws here are 1 mg and 1.5 mg, which keep the numbers in milligrams and show what a non-round amount does to the units. A 5 mg vial with 1 mL of bacteriostatic water is 5 mg/mL. A 1 mg draw is 0.2 mL, or 20 units on a U-100 syringe, and the vial holds five. A 1.5 mg draw at the same concentration is 0.3 mL, or 30 units, exactly the full barrel of a 0.3 mL syringe, and 5 divided by 1.5 gives three full draws with 0.5 mg left over. A 10 mg vial with 2 mL is also 5 mg/mL, so the units match and the vial holds ten 1 mg draws. With 1 mL in the 10 mg vial it is 10 mg/mL: 1 mg is 10 units and 1.5 mg is 15 units. Keeping both vial sizes at 5 mg/mL means one set of unit marks works for either.

Thymosin Alpha-1 questions

Thymosin alpha 1 dosage?

1.6 mg subcutaneously twice a week. That is the Zadaxin label dose, the dose in the 1998 hepatitis B trial and what most people copy. The label runs it 6 to 12 months; community cycles are usually 4 to 12 weeks.

How many units is 1.6 mg of thymosin alpha 1?

With 10 mg in 2 mL (5 mg/mL) 1.6 mg is 32 units. With 5 mg in 1 mL it is also 32 units. With 5 mg in 2 mL it is 64 units.

How many units is 1.5 mg of Thymosin Alpha-1 at 5 mg in 1 mL?

5 mg divided by 1 mL is 5 mg/mL. 1.5 mg divided by 5 mg/mL is 0.3 mL, which is 30 units on a U-100 syringe. The vial holds three full 1.5 mg draws with 0.5 mg left.

How much bacteriostatic water for a 10 mg vial of Thymosin Alpha-1?

Any volume the vial holds. 1 mL gives 10 mg/mL, 2 mL gives 5 mg/mL and 3 mL gives 3.33 mg/mL (rounded). A 1 mg draw is 10 units, 20 units or 30 units at those three concentrations.

How many 1 mg draws are in a 5 mg vial of Thymosin Alpha-1?

5 divided by 1 is 5 draws. With 1 mL of solvent (5 mg/mL) each 1 mg draw is 0.2 mL, or 20 units; with 2 mL (2.5 mg/mL) it is 0.4 mL, or 40 units.

Brands we recommend for Thymosin Alpha-1. We are independent and have no affiliation with any brand: no affiliate links, no referral codes, no paid placements. These are the suppliers whose testing and certificates hold up when we check them.