SS-31 (elamipretide) is a synthetic, mitochondria-targeting tetrapeptide developed by Hazel Szeto and Peter Schiller—its name comes from that origin (Szeto-Schiller peptide 31). It targets cardiolipin on the inner mitochondrial membrane and has been studied for mitochondrial dysfunction across a range of diseases. The FDA approved elamipretide (brand name Forzinity) for left ventricular dysfunction in adults with a rare mitochondrial condition caused by TAFAZZIN gene variants (Barth syndrome)—a narrow indication similar to how tesamorelin is approved.

Safety note. This article is educational and for personal recordkeeping only. It gives no dose, unit count, concentration, reconstitution, injection technique, vendor, cycle, or stacking instructions. Peptide decisions, especially gray-market or research-use products, belong with a licensed professional.

What is SS-31 and elamipretide?

SS-31 is a four-amino-acid peptide with alternating aromatic and basic residues (D-Arg-Dmt-Lys-Phe-NH2, where Dmt is 2′,6′-dimethyltyrosine). It accumulates in the inner mitochondrial membrane through an electrostatic interaction, protecting cardiolipin from oxidative modification—cardiolipin is critical to electron transport chain function. Clinical development through Stealth Biotherapeutics pursued it for several mitochondrial and cardiac conditions; the FDA approval of Forzinity for Barth syndrome represents that program’s narrowest, best-supported outcome.

Community use of SS-31 spans a much wider range: anti-aging, general mitochondrial optimization, cardiac support, exercise recovery, and kidney-injury contexts. That is the same gap as with tesamorelin—an approved drug for a specific rare indication, with gray-market vials promoted for off-label uses that are not what the clinical program studied. The approved indication does not validate the broader community claims, and a product outside a prescriber pathway is not the same product. For a broader safety frame, read Research Peptide Safety Questions Before You Start.

What do people use SS-31 and elamipretide for?

People most often mention SS-31 and elamipretide for mitochondrial function, fatigue, exercise tolerance, healthy aging, and pairing with NAD or MOTS-c discussions. Those are community claims, not proof. The same claim can mean very different things depending on whether it comes from a clinical label, a small trial, an animal model, a vendor page, or a forum anecdote.

Use the claim as a filing label, not a conclusion. Write down the purpose in plain language: what outcome is being watched, what else changed at the same time, and what would count as a reason to stop and ask for care.

How do people discuss using SS-31 and elamipretide?

Reported use usually means clinical-trial discussions, approved rare-disease product context, and off-label gray-market longevity claims. The useful part to record is context, not numbers: why it was considered, who reviewed it, what else was already in the stack, and what stop signs were discussed.

Do not copy online calculators, vendor protocols, or preparation walkthroughs into a personal plan. A peptide protocol log should preserve professional guidance and observations, not turn a social post into instructions.

What does the research say?

FDA approved Forzinity under accelerated approval for Barth syndrome in 2025. That narrow approval does not validate broad longevity or fatigue self-experimentation.

A good research note separates mechanism, animal data, human trial data, approval status, and real-world anecdotes. When those buckets get mixed together, a peptide can look more proven than it is.

What should a beginner track?

Track the exact reason it is being considered, fatigue and function baselines, clinician involvement, other mitochondrial products, and any reaction that needs prompt reporting.

In Dosefi’s peptide tracker, keep the entry boring and complete: date, category, source type, professional guidance, symptoms, photos only when useful, and the question you want answered next. A clear log is not proof that the peptide works. It is a way to avoid rewriting the story after the fact. If you are running other mitochondrial supplements alongside it — NAD precursors, for example — log those in the same tracker so you can see the full stack at a glance.

What red flags matter most?

A rare-disease prescription context is very different from a gray-market longevity stack. Product source, indication, monitoring, and adverse-event reporting all matter.

Also pause when a product is sold only through anonymous vendors, when a blend hides individual ingredients, when the seller offers medical claims without medical oversight, or when the only evidence is a before-and-after post. Serious symptoms should be handled as health events, not as content to troubleshoot in comments.

Sources