TL;DR: SS-31 (elamipretide) ships in 5mg, 10mg and 50mg vials. Reconstituted at PeptiMap’s reference volumes — 1mL, 2mL and 5mL of bacteriostatic water respectively — the 5mg and 10mg vials both land on 5mg/mL (50mcg per unit) and the 50mg vial lands on 10mg/mL (100mcg per unit). That means a 1mg draw is 20 units from the small vials and 10 units from the big one. The tables below cover every common dose; the SS-31 calculator does the same arithmetic for any volume you prefer.
The three vial sizes at a glance
The whole chart rests on one decision: how much bacteriostatic (BAC) water you add. PeptiMap uses these reference volumes because they keep the small and mid vials on an identical ruler, which makes cross-vial comparison trivial.
The practical consequence: if you have been working from a 5mg vial and step up to a 10mg vial, nothing on your syringe changes — you just get twice as many draws. Move to the 50mg vial and every unit count halves, because the concentration doubled.
The two formulas that drive every number
Everything below is these two lines, applied repeatedly.
mg/mL = vial strength (mg) ÷ BAC water added (mL)
mcg per unit = (mg/mL × 1000) ÷ 100
Worked example, 10mg vial with 2mL:
- Concentration: 10 ÷ 2 = 5 mg/mL = 5000 mcg/mL
- Per unit: 5000 ÷ 100 = 50 mcg per unit
- A 1mg (1000 mcg) draw: 1000 ÷ 50 = 20 units = 0.20 mL
Worked example, 50mg vial with 5mL:
- Concentration: 50 ÷ 5 = 10 mg/mL = 10000 mcg/mL
- Per unit: 10000 ÷ 100 = 100 mcg per unit
- The same 1mg draw: 1000 ÷ 100 = 10 units = 0.10 mL
20 units on a U-100 syringe = 0.20 mL = 1mg when the vial sits at 5mg/mL (5mg in 1mL, or 10mg in 2mL).
SS-31 dosage chart by vial size
Three tables, one per vial, all at the reference reconstitution volume. Doses-per-vial assumes no waste and full recovery.
5mg vial + 1mL BAC water = 5 mg/mL (50 mcg per unit)
| Target dose | Draw volume | U-100 units | Doses per vial |
|---|---|---|---|
| 250 mcg | 0.05 mL | 5 units | 20 |
| 500 mcg | 0.10 mL | 10 units | 10 |
| 1 mg | 0.20 mL | 20 units | 5 |
| 2 mg | 0.40 mL | 40 units | 2.5 |
| 2.5 mg | 0.50 mL | 50 units | 2 |
| 5 mg | 1.00 mL | 100 units | 1 |
10mg vial + 2mL BAC water = 5 mg/mL (50 mcg per unit)
| Target dose | Draw volume | U-100 units | Doses per vial |
|---|---|---|---|
| 250 mcg | 0.05 mL | 5 units | 40 |
| 500 mcg | 0.10 mL | 10 units | 20 |
| 1 mg | 0.20 mL | 20 units | 10 |
| 2 mg | 0.40 mL | 40 units | 5 |
| 2.5 mg | 0.50 mL | 50 units | 4 |
| 5 mg | 1.00 mL | 100 units | 2 |
50mg vial + 5mL BAC water = 10 mg/mL (100 mcg per unit)
| Target dose | Draw volume | U-100 units | Doses per vial |
|---|---|---|---|
| 500 mcg | 0.05 mL | 5 units | 100 |
| 1 mg | 0.10 mL | 10 units | 50 |
| 2.5 mg | 0.25 mL | 25 units | 20 |
| 5 mg | 0.50 mL | 50 units | 10 |
| 10 mg | 1.00 mL | 100 units | 5 |
| 20 mg | 2.00 mL | 200 units (two draws) | 2.5 |
Anything past 100 units is more than one U-100 barrel holds, so it becomes two draws — or a reason to reconstitute at a higher concentration instead.
Alternative reconstitution volumes
You are not locked to the reference volumes. Adding more water gives you finer resolution (more units per mg, easier to hit small doses accurately); adding less gives you compact draws. The peptide is identical either way — you are only choosing the ruler. This is the same principle laid out in the general reconstitution chart.
| Vial | BAC water | Concentration | mcg per unit | 1mg draw |
|---|---|---|---|---|
| 5mg | 1 mL | 5 mg/mL | 50 mcg | 20 units |
| 5mg | 2 mL | 2.5 mg/mL | 25 mcg | 40 units |
| 5mg | 2.5 mL | 2 mg/mL | 20 mcg | 50 units |
| 10mg | 1 mL | 10 mg/mL | 100 mcg | 10 units |
| 10mg | 2 mL | 5 mg/mL | 50 mcg | 20 units |
| 10mg | 3 mL | 3.33 mg/mL | 33.3 mcg | 30 units |
| 50mg | 3 mL | 16.67 mg/mL | 166.7 mcg | 6 units |
| 50mg | 5 mL | 10 mg/mL | 100 mcg | 10 units |
| 50mg | 10 mL | 5 mg/mL | 50 mcg | 20 units |
Weight-based dosing versus what a vial actually holds
SS-31 is usually quoted in research contexts at 0.1–0.5 mg/kg once daily. Scale that across body weights and the arithmetic is blunt:
| Body weight | 0.1 mg/kg | 0.25 mg/kg | 0.5 mg/kg |
|---|---|---|---|
| 60 kg | 6 mg | 15 mg | 30 mg |
| 70 kg | 7 mg | 17.5 mg | 35 mg |
| 80 kg | 8 mg | 20 mg | 40 mg |
| 90 kg | 9 mg | 22.5 mg | 45 mg |
| 100 kg | 10 mg | 25 mg | 50 mg |
Two things fall out of that table. First, the 0.5 mg/kg figure at 80 kg is 40 mg — which is exactly the fixed daily subcutaneous dose used in the human elamipretide programme (MMPOWER-3, TAZPOWER and its 168-week extension, and the 40 mg arm of PROGRESS-HF). The weight-scaled range is not arbitrary; its top end reconstructs the clinical dose for an average adult.
Second, at those magnitudes the vials stop making sense. A single 0.5 mg/kg dose for an 80 kg subject would empty an entire 50mg vial in a day and a quarter, and would need four full U-100 barrels per day at 10 mg/mL. A 5mg vial does not cover one such dose at all.
It is also worth being plain about the evidence: MMPOWER-3, the pivotal 218-participant phase 3 trial in primary mitochondrial myopathy, missed both primary endpoints (a −3.2 m difference on the six-minute walk test, p = 0.69). PROGRESS-HF found no left-ventricular volume benefit at either 4 mg or 40 mg. The positive signal that carried elamipretide to a 2025 accelerated approval came from Barth syndrome — a rare genetic cardiolipin disorder — not from healthy-ageing work. Longevity-adjacent SS-31 Dosierung claims remain preclinical. The wider comparison against MOTS-c is covered in mitochondrial peptides in 2026.
Doses per vial and the three-week stability window
Reconstituted SS-31 holds roughly 2–3 weeks refrigerated at 2–8 °C. That window, not the vial count, is often the real constraint — and it changes which vial size is the sensible buy.
| Vial | Recon volume | Doses at 500 mcg | Doses at 1 mg | Doses at 2.5 mg |
|---|---|---|---|---|
| 5mg | 1 mL | 10 | 5 | 2 |
| 10mg | 2 mL | 20 | 10 | 4 |
| 50mg | 5 mL | 100 | 50 | 20 |
At 500 mcg daily, a reconstituted 10mg vial runs 20 days — right at the edge of the stability window, which is a clean fit. A 50mg vial at the same dose would run 100 days, so most of it would degrade before use. The 50mg format only makes sense for multi-milligram daily draws, or for reconstituting in stages if the powder is split. Run your own numbers through the SS-31 calculator — enter vial strength, BAC volume and target dose and it returns mg/mL, mcg/unit and the exact syringe mark.
Frequently Asked Questions
How much BAC water do I add to a 10mg SS-31 vial?
2mL is the standard reference, giving 5mg/mL and 50 mcg per unit. That keeps the 10mg vial on the same ruler as a 5mg vial in 1mL, so unit counts carry over unchanged. Using 1mL instead doubles the strength to 10mg/mL and halves every draw.
How many units is 1mg of SS-31?
It depends entirely on concentration. At 5mg/mL (5mg in 1mL, or 10mg in 2mL) a 1mg dose is 20 units, or 0.20 mL. At 10mg/mL (50mg in 5mL) the same 1mg dose is only 10 units. Concentration decides units, never the vial label.
What is the typical SS-31 research dose?
Research references commonly cite 0.1–0.5 mg/kg once daily, and human elamipretide trials used a fixed 40 mg daily subcutaneous dose. In practice, vial-scale work sits far lower — roughly 250 mcg to 5 mg per draw — because a 5mg vial cannot cover a single weight-scaled dose.
Which SS-31 vial size should I choose?
Match the vial to your dose and the 2–3 week reconstituted shelf life. At 500 mcg daily, a 10mg vial in 2mL lasts about 20 days, which fits the window neatly. The 50mg vial only earns its size for multi-milligram daily draws.
Does the SS-31 dosaggio change between the 5mg and 10mg vial?
No, provided you reconstitute at the reference volumes. Both land on 5mg/mL, so a 1mg dose is 20 units from either. The only difference is how many doses the vial holds — five versus ten.
Is SS-31 dosing weight-based or fixed?
Both conventions circulate. The weight-based 0.1–0.5 mg/kg framing derives from preclinical rodent work; the human trial programme used a fixed 40 mg daily dose regardless of body weight. For vial-scale research, fixed low-milligram doses are the more workable of the two.
References
- Karaa A, Haas R, Goldstein A, et al. “Randomized dose-escalation trial of elamipretide in adults with primary mitochondrial myopathy.” Neurology, 2018;90(14):e1212-e1221. doi:10.1212/WNL.0000000000005255.
- Karaa A, Bertini E, Carelli V, et al. “Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial.” Neurology, 2023;101(3):e238-e252. doi:10.1212/WNL.0000000000207402.
- Thompson WR, Manuel R, Abbruscato A, et al. “Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER.” Genetics in Medicine, 2024;26(7):101138.
- Butler J, Khan MS, Anker SD, et al. “Effects of Elamipretide on Left Ventricular Function in Patients With Heart Failure With Reduced Ejection Fraction: The PROGRESS-HF Phase 2 Trial.” Journal of Cardiac Failure, 2020;26(5):429-437.
- Mitchell W, Ng EA, Tamucci JD, et al. “The mitochondria-targeted peptide SS-31 binds lipid bilayers and modulates surface electrostatics as a key component of its mechanism of action.” Journal of Biological Chemistry, 2020;295(21):7452-7469.
- Szeto HH. “First-in-class cardiolipin-protective compound as a therapeutic agent to restore mitochondrial bioenergetics.” British Journal of Pharmacology, 2014;171(8):2029-2050.
This article is a research and educational reference only; SS-31 sold as a research peptide is not an approved medicine, this is not medical advice, and it is not for human consumption.