Peptide LibrarySS-31 calculator
SS-31 is elamipretide, approved by the FDA as Forzinity at 40 mg once daily, but only for Barth syndrome in patients weighing at least 30 kg (20 mg with severe kidney impairment). Research vials are 10 or 50 mg, and 40 mg is a large amount for a peptide vial: it is four whole 10 mg vials, and more than one 1 mL syringe holds at every concentration below except 50 mg in 1 mL. The tables show that arithmetic.
Full research profile: SS-31. For any other concentration, use the insulin syringe units converter.
For research use only. Not medical advice. This page does arithmetic; it does not recommend an amount.
SS-31 reconstitution chart
Concentration and micrograms per mark on a U-100 insulin syringe, by vial size and water added. The peptide amount never changes; only how concentrated it is.
| Vial | + 1 mL water | + 2 mL water | + 3 mL water |
|---|---|---|---|
| 10 mg | 10 mg/mL · 100 mcg per unit | 5 mg/mL · 50 mcg per unit | 3.33 mg/mL · 33.3 mcg per unit |
| 50 mg | 50 mg/mL · 500 mcg per unit | 25 mg/mL · 250 mcg per unit | 16.67 mg/mL · 166.7 mcg per unit |
Most-listed SS-31 vial sizes across vendors we track: 10 mg (19 vendors), 50 mg (17 vendors), 25 mg (1 vendor), 100 mg (1 vendor). Compare prices.
SS-31 doses from the label and trials, in syringe units
The doses reported in each cited source, converted to U-100 syringe units at common vial and water combinations. This is arithmetic on the cited figures, not a recommendation; a dash means the amount is more than one full 1 mL syringe at that concentration.
Forzinity label: 40 mg once daily; 20 mg if eGFR is below 30 mL/min and not on dialysis (Barth syndrome, patients weighing at least 30 kg)
| Dose | 50 mg + 1 mL (50 mg/mL) | 50 mg + 2 mL (25 mg/mL) |
|---|---|---|
| 40 mg | 80 units (0.8 mL) | — |
| 20 mg | 40 units (0.4 mL) | 80 units (0.8 mL) |
Source: FORZINITY (elamipretide hydrochloride) prescribing information, DailyMed
Common questions
How many units is 40 mg of SS-31?
It depends on the concentration. In a 50 mg vial mixed with 1 mL of bacteriostatic water (50 mg/mL), 40 mg is 0.8 mL, or 80 units on a U-100 insulin syringe. With 2 mL of water instead, the same 40 mg is 160 units.
How much bacteriostatic water do you add to a 50 mg SS-31 vial?
There is no single correct volume: the amount of peptide is fixed and the water only sets the concentration. For 50 mg, 1 mL gives 50 mg/mL (500 mcg per unit), 2 mL gives 25 mg/mL (250 mcg per unit) and 3 mL gives 16.67 mg/mL (166.7 mcg per unit). More water makes each syringe mark hold less, which makes small amounts easier to measure accurately.
Are the SS-31 doses on this page recommendations?
No. They are the doses reported in the cited source (FORZINITY (elamipretide hydrochloride) prescribing information, DailyMed), converted to syringe units as arithmetic. Approved products come in their own strengths and devices, and what any person should use is a decision for a licensed clinician.
What does one unit on an insulin syringe mean?
A unit is a volume mark, not an amount of drug. On a U-100 syringe 100 units fill 1 mL, so 10 units is always 0.1 mL; how much peptide those 10 units hold depends only on the concentration you mixed. U-40 syringes use 40 marks per mL, so the same volume reads as a different number of units.