Vial Guide

SS-31 10 mg vial

How much bacteriostatic water to add to a 10 mg vial of SS-31, the syringe units for each common dose, and how many doses the vial holds.

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

The short answer

Mixed with 1 mL of bacteriostatic water, a 10 mg vial of SS-31 holds 10 mg/mL. A 5 mg dose is then 50 units (0.50 mL) on a U-100 insulin syringe, and the vial holds about 2 doses of that size. Taken 1× per day, it lasts about 2 days.

Approved drug. FDA accelerated approval in 2025 as Forzinity, for muscle strength in Barth syndrome (a rare mitochondrial disease). Other uses are unproven.
SS-31 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 5 mg
1 mL10 mg/mL100 mcg50 units (0.50 mL)
2 mL5 mg/mL50 mcg100 units (1.00 mL)
3 mL3.333 mg/mL33.3 mcg1.50 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
1 mg
2 mg
4 mg
5 mg
6 mg
10 mg
25 mg–––
40 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

  • Label 40 mg once daily; 20 mg if eGFR is under 30 and not on dialysis. The label sets no dose for people on dialysis.
  • Community 1–10 mg once daily for general use.

Doses are what labels, trials or community reports reference, not recommendations. SS-31’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 1 mLDraw 1 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, 10 mg/mL, on the vial.

Storage: Powder: −20 °C. Mixed: 2–8 °C, protected from light.

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 SS-31?

There’s no single right amount: the water only sets the strength. With 1 mL of bacteriostatic water, a 10 mg vial holds 10 mg/mL. With 2 mL it’s 5 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 5 mg of SS-31?

With 1 mL in a 10 mg vial, 5 mg is 50 units (0.50 mL) on a U-100 insulin syringe. With 2 mL, 100 units (1.00 mL); with 3 mL, 1.50 mL.

How many doses are in a 10 mg vial of SS-31?

About 2 doses of 5 mg, or 0 of 25 mg or 0 of 40 mg. Taken 1× per day at 5 mg, it lasts about 2 days.

How long does a mixed vial of SS-31 keep?

Powder: −20 °C. Mixed: 2–8 °C, protected from light.

Other vial sizes

Sources

  • Forzinity (elamipretide) prescribing information (FDA)

The math on this page uses the doses and storage on SS-31’s page.