PeptideCalculations
mitochondria-targeted tetrapeptide

SS-31 dosage

SS-31 is elamipretide, approved by the FDA in September 2025 as Forzinity for Barth syndrome at 40 mg subcutaneous once a day. Trials in heart failure and mitochondrial myopathy used similar daily doses. Community use is 5 to 10 mg a day, a fraction of the label dose, in 4 to 8 week blocks. Injection site reactions hit every patient in the pivotal trial, so rotate sites.

By the Peptide Calculations editors · Updated 2026-10-19 · Studied for Barth syndrome muscle strength (FDA accelerated approval 2025), mitochondrial myopathy, heart failure and dry AMD trials

Dose
40 mg once daily
per day · FDA label
How often
once daily
morning; skip a missed dose, do not double (label)
How long
label: continuous
community: 4 to 8 weeks on, 4 weeks off
Route
subcutaneous
abdomen, rotating sites

1Dose ranges by source

RangePerBasisNote
40 mg once dailydayFDA label
FDA label
Forzinity, subcutaneous, patients 30 kg and over; 20 mg daily with severe kidney impairment
5 mg to 10 mg per daydayCommonly reported
commonly reported
subcutaneous, 4 to 8 weeks; no trial at this dose

2Dose to units chart

50 mg vial + 2 mL bacteriostatic water = 25 mg/mL, so each unit on a U-100 insulin syringe holds 250 mcg.

DoseDraw (mL)UnitsDoses in vial
40 mg1.61601
50 mg22001
Open in the SS-31 calculatorFull 50 mg + 2 mL table

50 mg + 2 mL = 25 mg/mL, so 5 mg = 0.2 mL = 20 units and 10 mg = 40 units. A 10 mg vial + 1 mL is 10 mg/mL: 5 mg = 50 units.

3Commonly stacked with

MOTS-c · 0.5 mg/kg to 5 mg/kg

4Side effects

injection site redness (100% in the trial), pain (75%), swelling and itching (67%)allergic reactions including serious ones (label warning)headache (reported)dizziness (reported)
Before you start. The approval is accelerated and the randomized part of the pivotal trial did not beat placebo on its primary endpoints; the FDA requires a confirmatory trial. The label warns of hypersensitivity reactions. The community dose has no efficacy data at all. Not medical advice. Talk to a clinician and start low.

Storage: lyophilized: fridge; reconstituted: fridge, use within 4 weeks (commonly reported); Forzinity vials are refrigerated

5SS-31 dosage questions

SS-31 dosage?

The FDA label for Forzinity is 40 mg subcutaneous once a day for Barth syndrome. Community users take 5 to 10 mg a day for 4 to 8 weeks, which has no trial behind it. If the point is mitochondrial support in a healthy person, nobody has shown the low dose does anything.

How many units of SS-31 is 5 mg?

With 50 mg in 2 mL (25 mg/mL) 5 mg is 20 units and 10 mg is 40 units. With a 10 mg vial in 1 mL, 5 mg is 50 units.

Is SS-31 FDA approved?

Yes, as Forzinity (elamipretide) since September 2025, under accelerated approval for Barth syndrome only. The randomized part of the trial did not beat placebo on its main endpoints; approval rested on muscle strength gains in the open-label extension.

What are the side effects of SS-31?

Injection site reactions, mainly. In the pivotal trial every patient had redness, three quarters had pain and two thirds had swelling or itching. The label also warns of allergic reactions, some needing emergency care.

6Sources

  1. FDA Drug Trials Snapshot, FORZINITY (elamipretide), approved September 19, 2025, 40 mg subcutaneous once daily, SPIBA-201 trial
  2. Drugs.com, Forzinity prescribing information
  3. Peptide Protocol Wiki, SS-31 dosing (community ranges)

Educational summary of published labels, trials and commonly reported use. Not medical advice.

Brands we recommend for SS-31Independent. No affiliation with any brand, no affiliate links, no referral codes, no paid placements.
  1. 1Licensed Peptides two accredited labs on every lot, certificates public, card and Apple Pay checkout
  2. 2Core Peptides long track record, public certificates, wide catalog
  3. 3Ascension Peptides public third-party testing, clear pricing