SS-31 (elamipretide)

What SS-31 (elamipretide) does

SS-31 is elamipretide, which binds a fat in mitochondria. Forzinity has accelerated US approval for Barth syndrome muscle strength in patients weighing at least 30 kg; benefit needs confirmation. Mitochondrial myopathy and dry macular degeneration trials missed their main goals. Injection-site reactions are common; serious allergies can occur.

• Forzinity is approved for muscle strength in people with Barth syndrome who weigh at least 30 kg; the benefit still needs confirming. (Drug label)
• In a long-term follow-up of people with Barth syndrome, walking gains lasted in the eight who stayed on it. (Studied in a trial)
• People report more energy and longer workouts, though others notice no clear effect. (Reported by users)

Uses in the sources

• Forzinity has accelerated US approval for muscle strength in Barth syndrome patients weighing at least 30 kg. Clinical benefit needs confirmation in another trial. (Drug label) (source)
• Studied for primary mitochondrial myopathy. The 218-person MMPOWER-3 trial did not improve walking distance or fatigue versus placebo. (Studied in a trial) (source)
• Studied for heart and eye diseases; several randomized trials missed their main outcomes. These uses have no approved elamipretide indication. (Studied in a trial) (source)
• Used online for energy, healthy aging and recovery. No trial has shown longer life or a lasting performance benefit in healthy adults. (Reported by users) (source)
• People with ME/CFS or long COVID report benefits, no effect or worse symptoms. No controlled disease-specific trial was found. (Reported by users) (source)

SS-31 (elamipretide) dosage

Typical reported dose: 40 mg once a day

• Forzinity: labelled daily dose: 40 mg subcutaneously once daily once daily, under the skin. Drug label. Studied in: Barth syndrome, body weight at least 30 kg. (source)
• Forzinity: severe kidney impairment: 20 mg subcutaneously once daily once daily, under the skin. Drug label. Studied in: Adults with Barth syndrome, ≥30 kg, eGFR <30 mL/minute and not on dialysis. (source)
• MMPOWER: low IV dose: 0.01 mg/kg/hour IV for 2 hours daily; 0.02 mg/kg total per day once daily as a 2-hour infusion, into a vein. Studied in a trial. Studied in: Adults with genetically confirmed primary mitochondrial myopathy. (source)
• MMPOWER: middle IV dose: 0.1 mg/kg/hour IV for 2 hours daily; 0.2 mg/kg total per day once daily as a 2-hour infusion, into a vein. Studied in a trial. Studied in: Adults with genetically confirmed primary mitochondrial myopathy. (source)
• MMPOWER: high IV dose: 0.25 mg/kg/hour IV for 2 hours daily; 0.5 mg/kg total per day once daily as a 2-hour infusion, into a vein. Studied in a trial. Studied in: Adults with genetically confirmed primary mitochondrial myopathy. (source)
• MMPOWER-2: 40 mg: 40 mg SC once daily once daily, under the skin. Studied in a trial. Studied in: Adults with genetically confirmed primary mitochondrial myopathy. (source)

These are doses reported in labels, trials or user reports, not a personal plan. Check the source behind each one.

Work out syringe units with the dosing calculator

How to store SS-31 (elamipretide)

Comes as: Ready-to-use sterile injection: 280 mg in 3.5 mL (80 mg/mL), single-patient-use vial.

Mixed with: Forzinity comes ready to use. Do not add water..

Common vial sizes: 280 mg. Common water amounts: mL.

• Do not mix other products in the same syringe.
• Use clear, colorless-to-yellow solution only; reject cloudiness or particles.

Before mixing: Unopened Forzinity: refrigerate at 2–8°C. Do not freeze.

After mixing: After first use: refrigerate at 2–8°C or store at room temperature, 20–25°C. Discard 8 days after first opening.

Forzinity ready-made solution: refrigerate at 2-8 C; do not freeze. After opening, keep at 2-8 C or 20-25 C and discard the vial after eight days.

SS-31 (elamipretide) side effects and risks

Reported side effects

• Injection-site redness: Barth label: 12/12 (100%) active vs 3/12 (25%) placebo., mild. Rotate sites daily; avoid inflamed skin. (source)
• Injection-site pain: Barth label: 9/12 (75%) vs 5/12 (42%)., mild. Persistent or worsening reactions need review. (source)
• Injection-site firmness or itch: Each: 8/12 (67%) active vs 2/12 (17%) placebo., mild (source)
• Injection-site bruising or hives: Each: 3/12 (25%) active vs 0 placebo., moderate (source)
• Increased eosinophils, white blood cells: ReCLAIM 2: 7/117 (6.0%) vs 0/59 placebo. Label: frequent rises in studies lasting at least 30 days., mild (source)
• Serious allergic reaction: Can start minutes to months after treatment begins; frequency unknown., serious. Stop further doses and seek emergency care. (source)
• Flushing, dizziness or low blood pressure: Label overdose symptoms may be histamine related; community flushing has no reliable rate., moderate (source)
• Anxiety, stimulation or worsened fatigue: Personal reports only; frequency and causation are unknown., moderate (source)

Stop and get help if

• Trouble breathing, throat swelling, widespread hives or fainting after a dose: Stop further doses and seek emergency care now; a serious allergic reaction can need epinephrine.
• Marked lightheadedness, collapse or suspected overdose: Hold further doses and seek urgent medical assessment; overdose may cause low blood pressure.
• New severe or persistent abdominal pain, especially with vomiting: Seek urgent assessment; a pediatric report described pancreatic-enzyme elevation, but causation is uncertain.
• Cloudy vial, particles, fever or spreading hot, painful injection-site redness: Do not use the vial; seek prompt care for possible infection or product contamination.

Who should avoid it

• pregnant: No human pregnancy data. the FDA label does not list pregnancy as a formal contraindication.
• breastfeeding: No human milk or infant-effect data.
• tryingToConceive: Human reproductive safety is unknown.
• under18: The FDA label separately allows Barth syndrome patients weighing at least 30 kg.
• other: Do not restart after a serious allergy to elamipretide or a product ingredient.
• other: Safety and effectiveness below 30 kg are not established; no approved dose exists for this weight group.
• kidneyDisease: Kidney disease raises drug levels. Adults with estimated filtration below 30 mL/min need dosing review; dialysis dosing is unknown.
• heartCondition: Heart-failure trials do not establish general benefit. New chest pain, fainting or worsening breathlessness need prompt care.
• liverDisease: No liver dosing study was found. The label expects little change in drug levels; severe disease needs review.
• testedAthlete: Elamipretide is not named in the 2026 list. Its post-approval classification is unconfirmed; ask the sport’s anti-doping authority.

Interactions

• Aspirin and clopidogrel: Single-dose IV studies found no significant change in drug levels or blood-thinning effects. Other blood thinners remain uncertain.
• Unfractionated heparin: The IV study found no significant change in clotting tests, aPTT and anti-Xa. Continue usual monitoring.
• Metformin and other MATE1 substrates: In lab tests, elamipretide blocks MATE1, a protein that moves medicines. Effects on metformin in people remain unknown.
• Duplicate elamipretide products: These names mean the same peptide. Combining them can duplicate the dose. Do not mix products in one syringe.
• MOTS-c and other experimental energy stacks: No controlled human combination trial was found. Multiple changes make side effects and benefits hard to trace.

Product quality risks

• FDA documented mislisting and quality-control failures in an API supply chain that included elamipretide acetate; this did not measure all retail SS-31 vials.
• Unknown powders can have the wrong identity, amount or impurities; HPLC purity alone does not prove sterility or absence of bacterial toxins.
• No independent SS-31 retail-vial assay survey or confirmed SS-31 counterfeit-product series was located. Generic peptide warnings are not SS-31 incidence data.

What to expect

• First 12 weeks, Barth syndrome trial: In the small Barth syndrome trial, injection-site reactions were common and daily elamipretide did not beat placebo on walking or fatigue at 12 weeks.
• Extension weeks 12-24: Knee strength rose during the uncontrolled Barth syndrome extension, which cannot separate drug effects from other changes.
• Extension week 168: Eight remaining Barth syndrome participants still showed knee-strength gains, but there was no placebo group for comparison.

Forzinity is used daily for eligible people with Barth syndrome; its label gives no fixed cycle.

45 human records include ongoing trials: 28 registered treatment studies, 9 other FDA studies, 7 case reports or series and 1 historical comparison. Records can share participants.

Key studies

• TAZPOWER: Barth crossover: The randomized phase failed; later uncontrolled muscle-strength gains supported accelerated approval. (source)
• TAZPOWER: long extension: Walking gains persisted among eight long-term completers. (source)
• MMPOWER: IV dose finding: The unadjusted main comparison narrowly missed significance. (source)
• MMPOWER-2: daily injections: The walking endpoint missed; several fatigue measures improved. (source)
• MMPOWER-3: phase 3: Neither walking distance nor fatigue improved versus placebo. (source)
• MMPOWER-3: genetic subgroups: Post hoc genetic signals led to NuPOWER. (source)

SS-31 (elamipretide) FAQ

• Is SS-31 (elamipretide) FDA-approved? Yes: Forzinity (improve muscle strength in adults and children with Barth syndrome weighing at least 30 kg.). Accelerated approval 2025-09-19; benefit still needs confirmation. No SS-31-specific bulks-list inclusion or PCAC decision was found; July’s peptide agenda did not include it.
• How do people take it? Under the skin, once daily. Ongoing; label gives no cycle. Source: drug label.
• What's the difference between SS-31 (elamipretide) and MOTS-c? SS-31 (elamipretide): a peptide approved for Barth syndrome muscle strength; benefit needs confirmation and broader energy benefits remain unproven. MOTS-c: a peptide the body makes; injection benefits and safety remain unproven. Why people pair them: people use it together with SS-31 or after an SS-31 “primer,” hoping for more energy. No controlled human combination trial was found.
• Can I take it with MOTS-c? People use it together with SS-31 or after an SS-31 “primer,” hoping for more energy. No controlled human combination trial was found. Combined safety and the claimed need to repair mitochondria before MOTS-c are unproven. Source: reported by users. Ask a doctor before combining anything.
• Is it banned in sport? It is unclear (WADA 2026). Not named in the 2026 list. S0 concerns drugs without any human approval; ask the anti-doping authority for a specific ruling.
• How do I store it once opened? After first use: refrigerate at 2–8°C or store at room temperature, 20–25°C. Discard 8 days after first opening.