SS-31 (elamipretide, brand name Forzinity) is the first FDA-approved drug that directly targets your mitochondria. It goes straight to the inner wall of your mitochondria and fixes the assembly line that makes energy. Basically makes your cells' power plants run like they did ten years ago. The Barth syndrome approval (September 2025) is narrow, but the mechanism is relevant to anyone whose energy isn't what it used to be. The difference between SS-31 and MOTS-c is where they work. MOTS-c activates AMPK from the outside, mimicking exercise. SS-31 goes inside the mitochondria and fixes the machinery directly, stabilizing the inner membrane where ATP is actually produced. The clinical dose (40mg) is expensive. Community protocols use 5-20mg.
SS-31 (Elamipretide) Protocol
Dose: 40mg SubQ daily (FDA-approved dose for Barth). The longevity crowd uses 5-20mg for longevity protocols. | Frequency: Once daily | Cycle: Continuous in clinical setting. Community protocols often run 4-8 week cycles. | Route: SubQ
Reconstitution: 1mL bacteriostatic water per 10mg vial (10mg/mL). For 50mg vials, 2.5mL gives 20mg/mL.. Free reconstitution calculator.
The FDA dose is 40mg which is aggressive and expensive. The longevity community typically uses much lower doses. This is one where the clinical dose and the community dose are very different animals.
SS-31 (Elamipretide) Effects
Mitochondrial function (80%). Makes your mitochondria better at converting fuel into energy. The older your cells are, the more they need this tune-up. This is the core mechanism.
Muscle strength (65%). The FDA approval endpoint. Your muscles get stronger because your cells are making more energy.
Exercise capacity (55%). Better cellular energy = you can push harder and crash less
Cellular energy (50%). General improvement in how much energy your cells produce (ATP, the fuel everything runs on). People describe feeling less tired across the board.
SS-31 (Elamipretide) Side Effects
Injection-site reactions (25%). Red, swollen, or sore where you pinned. Most common side effect in trials. Rotate your sites.
Nausea (10%). Mild nausea for some people. Comes and goes. Not a pattern, just your body adjusting.
Headache (8%). Occasional headache. Doesn't seem related to dose. Just happens sometimes early on.
SS-31 (Elamipretide) Dosing by Use Case
Condition
Dose
Duration
Notes
Mitochondrial restoration and longevity
5-20mg SubQ daily
4-8 week cycles
The primary off-label use case. SS-31 stabilizes cardiolipin on the inner mitochondrial membrane, restoring the energy-making machinery that gets slower every year you're alive. Community doses are well below the 40mg FDA dose. Start at 5mg and assess. The mechanism is the same at lower doses, just lower magnitude.
Exercise capacity and muscle function
10-20mg SubQ daily
4-8 weeks
The FDA approval was based on muscle strength improvement (TAZPOWER trial). Single-dose human data showed improved muscle energy output in older adults (Roshanravan et al. 2021). This is for the person whose gym capacity is declining faster than their effort level explains.
Cardiac function support
20-40mg SubQ daily
Clinical supervision recommended
Animal data shows improved heart pumping function in heart failure models (Sabbah et al. 2016). EMBRACE-STEMI and PROGRESS-HF trials tested elamipretide in human cardiac patients. Results were mixed for the primary endpoints, but mitochondrial function biomarkers improved. This is clinical territory. Don't self-prescribe for heart conditions.
Stacked with MOTS-c for full mitochondrial protocol
5-10mg SS-31 + 5mg MOTS-c 2-3x/week
8-12 weeks
Different mechanisms, same organelle. MOTS-c flips the exercise switch from the outside. SS-31 goes inside and stabilizes the inner membrane where ATP is produced. Together they address mitochondrial function from both sides. The community calls this the full mito stack.
SS-31 (Elamipretide) Results Timeline
Week 1-2, Subtle shifts: You might not feel much. The mitochondrial changes are happening at a cellular level before you notice them systemically. Some people report slightly better sleep or less afternoon fatigue. The single-dose human study showed improved ATP production within hours, but subjective energy changes take longer.
Week 2-4, Energy baseline lifting: Less systemic tiredness. Exercise tolerance improves. Recovery between sessions shortens. The effect is subtle but cumulative. You're not wired. You just don't hit the wall as early.
Week 4-6, Peak mitochondrial benefits: Full effect for a cycle. Muscle function at its best. Fatigue resistance improved. If you're tracking labs (lactate, VO2 max proxy), the numbers may move. This is where people decide whether to continue or cycle off.
Week 6-8+, Cycle off or continue: Community protocols typically cycle off at 4-8 weeks. No withdrawal effects. The mitochondrial improvements may persist for weeks after stopping. Clinical protocols (Barth syndrome) are continuous. No consensus on ideal long-term cycling for off-label use.
Frequently Asked Questions About SS-31 (Elamipretide)
What is SS-31?
SS-31 (elamipretide) is a four-amino-acid peptide that goes straight into your mitochondria and fixes the inner wall where energy is made. That wall (called cardiolipin) holds together the machinery that produces ATP, your cells' fuel. When it gets damaged from aging and stress, energy output drops. SS-31 stabilizes it and gets the machinery running properly again. It received FDA accelerated approval in September 2025 as Forzinity for Barth syndrome, making it the first approved mitochondria-targeted therapeutic.
What is the best SS-31 dosage?
The FDA-approved dose for Barth syndrome is 40mg SubQ daily. The longevity crowd uses 5-20mg daily. There are no published human dosing trials for healthy individuals. The single-dose study in older adults (Roshanravan et al.) used IV elamipretide and showed improved skeletal muscle ATP production. For SubQ community protocols, 5-10mg daily for 4-8 weeks is the most common range. Start low. The mechanism works at lower doses.
What are the side effects of SS-31?
Injection-site reactions (25%) are the most common. Redness, swelling, or soreness where you pinned. Nausea (10%) and headache (8%) early on. In the TAZPOWER trial at the full 40mg dose, these rates were higher. At community doses (5-20mg), side effects are generally milder. No serious adverse events have been widely reported among people using it. SS-31 is a tetrapeptide, not a synthetic drug. Your body breaks it down into amino acids.
SS-31 vs MOTS-c: what's the difference?
Same organelle, different mechanism. MOTS-c activates AMPK from outside the mitochondria, mimicking the metabolic effects of exercise. It improves insulin sensitivity and glucose handling. SS-31 goes inside the mitochondria and stabilizes the inner membrane (cardiolipin) where ATP is actually produced. MOTS-c is the exercise mimetic. SS-31 is the repair mechanic. Some protocols stack both for full mitochondrial coverage: MOTS-c for the metabolic signaling, SS-31 for the structural repair.
Is SS-31 FDA-approved?
Yes, for one specific indication. Elamipretide received FDA accelerated approval on September 19, 2025 for Barth syndrome, a rare genetic mitochondrial disorder. The brand name is Forzinity. This makes it the first FDA-approved drug that directly targets mitochondria. The approval validates the mechanism (cardiolipin stabilization improves mitochondrial function in humans), but it does not mean it's approved for longevity, anti-aging, or general use. The longevity crowd uses compounded elamipretide off-label.
How do you reconstitute SS-31?
For a 10mg vial: add 1mL of bacteriostatic water. That gives you 10mg per mL. For a 5mg dose, draw 50 units on a U-100 insulin syringe. For 10mg, draw 100 units (the whole mL). For 50mg vials: add 2.5mL to get 20mg/mL. Aim the water at the glass wall. Swirl gently. Never shake. SS-31 is a small tetrapeptide and dissolves quickly. Refrigerate after reconstitution. Use within 4 weeks.
What is cardiolipin and why does it matter?
Cardiolipin is a special fat molecule found only on the inner wall of your mitochondria. It holds together the protein machinery (Complexes I through V) that actually produces ATP, your cells' energy currency. When cardiolipin is oxidized or degraded (which happens with aging, oxidative stress, and mitochondrial disease), the electron transport chain becomes less efficient. ATP output drops. That's the cellular version of 'I'm tired all the time.' SS-31 binds to cardiolipin, prevents its oxidation, and restores the structural organization of the electron transport chain.
How long does it take for SS-31 to work?
The single-dose human study showed improved skeletal muscle ATP production within hours of IV administration. Subjective energy improvements typically take 1-2 weeks. Exercise capacity changes become noticeable at 2-4 weeks. Full cycle benefits at 4-6 weeks. The effects are subtle and cumulative. You're not going to feel a rush. You'll notice you're less tired, recover faster, and hit the wall later in workouts. If you're tracking, check pre- and post-cycle VO2 max or grip strength.
Strong evidence. FDA accelerated approval September 19, 2025 for Barth syndrome under the brand name Forzinity. The first approved drug that directly targets mitochondria. The TAZPOWER trial used 40mg SubQ daily. Approval was based on improved knee extensor muscle strength. Continued approval contingent on a confirmatory trial, but the regulatory bar has been cleared.
Approval status: FDA accelerated approval (Sept 2025) for Barth syndrome
References
Reid Thompson W, Hornby B, Manuel R, et al. A phase 2/3 randomized clinical trial followed by an open-label extension to evaluate the effectiveness of elamipretide in Barth syndrome. Genet Med, 2021. PMID 33077895
Roshanravan B, Liu SZ, Ali AS, et al. In vivo mitochondrial ATP production is improved in older adult skeletal muscle after a single dose of elamipretide in a randomized trial. PLoS One, 2021. PMID 34264994
Karaa A, Haas R, Goldstein A, et al. Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial. Neurology, 2023. PMID 37268435
Karaa A, Haas R, Goldstein A, et al. A randomized crossover trial of elamipretide in adults with primary mitochondrial myopathy. J Cachexia Sarcopenia Muscle, 2020. PMID 32096613
Sabbah HN, Gupta RC, Kohli S, et al. Chronic Therapy With Elamipretide (MTP-131), a Novel Mitochondria-Targeting Peptide, Improves Left Ventricular and Mitochondrial Function in Dogs With Advanced Heart Failure. Circ Heart Fail, 2016. PMID 26839394
Karaa A, Goldstein A, Engel W, et al. Randomized dose-escalation trial of elamipretide in adults with primary mitochondrial myopathy. Neurology, 2018. PMID 29500292
Storage
Lyophilized: Freeze at -20C for long-term storage. Stable for 2+ years. Refrigerate for short-term.
Reconstituted: Refrigerate at 2-8C. Use within 4 weeks. Do not freeze.
Water: Bacteriostatic water. 1mL per 10mg vial is standard.
Needle: 29-30 gauge, 0.5 inch for SubQ injection
These statements have not been evaluated by the FDA. This content is for educational purposes only. Consult a healthcare professional before starting any protocol. vialprep sells injection supplies, not compounds.
