Vial Guide

TB-500 10 mg vial

How much bacteriostatic water to add to a 10 mg vial of TB-500, the syringe units for each common dose, and how many doses the vial holds.

Water
2 mL
Strength
5 mg/mL
Common dose
2.5 mg
Draw
50 units0.50 mL
Doses per vial
4

The short answer

Mixed with 2 mL of bacteriostatic water, a 10 mg vial of TB-500 holds 5 mg/mL. A 2.5 mg dose is then 50 units (0.50 mL) on a U-100 insulin syringe, and the vial holds about 4 doses of that size. Taken 2× per week, it lasts about 2 weeks.

Preclinical. The fragment has never been tested in humans. Human trials used full-length thymosin beta-4, a different molecule.
TB-500 page

How much water

The water only sets the strength; the dose and the number of doses in the vial stay the same. Draws are on a U-100 insulin syringe, where 1 unit is 0.01 mL.

Water addedStrengthPer syringe unitDraw for 2.5 mg
1 mL10 mg/mL100 mcg25 units (0.25 mL)
2 mL5 mg/mL50 mcg50 units (0.50 mL)
3 mL3.333 mg/mL33.3 mcg75 units (0.75 mL)

Dose chart

Syringe units for each common dose at each water volume. Select a cell to open it in the calculator.

DoseWater added
1 mL2 mL3 mL
2 mg
2.5 mg
5 mg

Draws over 100 units show in mL. Faded values are under 2 units, which is hard to measure. Check that your vial holds the larger volumes.

Where the doses come from

  • Community Loading: 2–2.5 mg twice weekly for 4–6 weeks.
  • Community Maintenance: 2–2.5 mg once weekly or every 2 weeks.

Doses are what labels, trials or community reports reference, not recommendations. TB-500’s page has the cycle, side effects, cautions and sources.

Mixing and storage

  1. PrepareLet a refrigerated vial come to room temperature, and wipe both stoppers with an alcohol swab.
  2. Add 2 mLDraw 2 mL of bacteriostatic water and let it run slowly down the inside wall of the vial.
  3. Swirl, don’t shakeSwirl gently until the powder dissolves and the liquid is clear.
  4. Label itWrite the date and the strength, 5 mg/mL, on the vial.

Storage: Powder: 2–8 °C, or −20 °C long-term. Mixed: 2–8 °C, use within 2–4 weeks.

The reconstitution guide covers each step, and the units page explains syringe markings.

Questions

How much water do I add to a 10 mg vial of TB-500?

There’s no single right amount: the water only sets the strength. With 2 mL of bacteriostatic water, a 10 mg vial holds 5 mg/mL. With 1 mL it’s 10 mg/mL; with 3 mL it’s 3.333 mg/mL. Less liquid makes each dose a smaller draw; more makes small doses easier to measure.

How many units is 2.5 mg of TB-500?

With 2 mL in a 10 mg vial, 2.5 mg is 50 units (0.50 mL) on a U-100 insulin syringe. With 1 mL, 25 units (0.25 mL); with 3 mL, 75 units (0.75 mL).

How many doses are in a 10 mg vial of TB-500?

About 4 doses of 2.5 mg, or 5 of 2 mg or 2 of 5 mg. Taken 2× per week at 2.5 mg, it lasts about 2 weeks.

How long does a mixed vial of TB-500 keep?

Powder: 2–8 °C, or −20 °C long-term. Mixed: 2–8 °C, use within 2–4 weeks.

Other vial sizes

Sources

  • Characterization of the TB-500 fragment (PubMed) PMID 22962027
  • IV thymosin beta-4 in healthy volunteers, Phase 1 (PubMed) PMID 20536472
  • FDA advisory committee backs 6 peptides for compounding (AJMC, July 2026)

The math on this page uses the doses and storage on TB-500’s page.