# SS-31

Mitochondrial cardiolipin binder; FDA-approved for Barth syndrome, popular for energy and endurance.

- Page: https://peprank.xyz/peptides/ss-31
- Category: Mitochondria & longevity (Research peptide)
- Also known as: elamipretide; Forzinity; MTP-131; Bendavia
- Routes: Injection
- Sequence: RYKF (elamipretide: D-Arg1, 2',6'-dimethyl-Tyr2 (Dmt), C-amide)
- Safety tier: Strict: Avoid · Balanced: Avoid · Evidence only: Avoid
- Risk axes (0 none to 3 severe): Seen harm 2, Mechanism 1, Data gap 1, Silent harm 1, Product 3
- Positive: 52% of 50 graded reports glowing or positive, shrunk toward the 49% all-report average by 8 reports' weight
- Rank: #32 of 61 research peptides
- Graded reports: 50 (Glowing 9, Positive 17, Mixed 5, Nothing 8, Negative 6, Bad reaction 5)
- Evidence: Approved drug — approved in US (accelerated approval Sept 2025, Barth syndrome, 40 mg/day); human RCTs in mitochondrial myopathy and heart failure were mostly negative on efficacy but showed clean safety
- Access: Grey market
- Onset: Responders often feel more energy within 1-3 days; many first go through 1-3 weeks of afternoon fatigue, and vision, nerve or PEM changes are reported after 2-6 weeks.
- Lasts: cumulative; users say gains fade within weeks of stopping
- Cost per month: ≈ €71–350 (at 1–5 mg/day, Semax Polska at €2.37/mg)
- Dose users report: 2–5 mg/day (median 2.9 mg, n=24)
- Updated: 2026-10-30

## What users report

Responders describe clean, steady energy, fewer PEM crashes in long COVID, and scattered striking anecdotes (smell returning, feeling back in a long-numb foot, sharper vision, lower fasting glucose), usually within days to two weeks. About half of first-hand reports are positive. A fifth notice nothing even after 8-week runs or repeated cycles, and another fifth feel worse: afternoon fatigue crashes for the first 1-3 weeks, flu-like days, or, mostly in ME/CFS and dysautonomia, dizziness, palpitations and anxiety even at 0.1-0.2 mg. Many run it as a 'reset' before MOTS-c, and pharmacology-minded commenters point out that the trials only showed benefit in sick mitochondria. The cost of the 2-5 mg/day doses people use is the most common complaint.

**Effects:** more daytime energy; better exercise endurance; less fatigue in ME/CFS / long-COVID; joint 'clunks' easing (anecdotal); vision changes (scattered anecdotes, unverified)

**Downsides:** injection-site redness/itch (very common in trials); a few days of tiredness at the start; expensive at community doses; headache

**Risks:** Generic: grey-market purity/endotoxin risk is amplified by the large mg doses users inject; Hypersensitivity is possible as with any injected peptide; nothing compound-specific in trials

**Typical use:** Community: 1-5 mg/day subQ for 4-8 weeks (some 10 mg/day for 10 days); the approved dose is 40 mg/day.

**Getting it:** Forzinity is a Barth-only specialty drug; most users buy research vials, mostly from China since US vendors were pressured in late 2025.

**Stacked with:** MOTS-c (The most common pairing: 2-8 weeks of SS-31 as a mitochondrial 'repair' phase, then MOTS-c, or both together at 1-2 mg/day.); NAD+ (Run alongside SS-31 and MOTS-c as a three-part 'mito stack', especially by long-COVID users.); Retatrutide or tirzepatide (Many add SS-31 during a GLP-1 cut for gym energy, which makes its own effect hard to separate.)

## Risk profile

- **Seen harm 2/3:** The Forzinity label warns of serious hypersensitivity, from minutes to months after starting, after FDA counted three serious cases; in trials injection-site reactions were near-universal and eosinophilia common. First-hand reports add large welts and autonomic flares.
- **Mechanism 1/3:** Binds cardiolipin in the inner mitochondrial membrane; no pharmacological pathway to serious harm is known, and the label's hypersensitivity and eosinophilia point to immune sensitisation rather than a drug action.
- **Data gap 1/3:** FDA accelerated approval in 2025 for Barth syndrome on a 12-patient pivotal trial, backed by RCTs of 218 and 176 patients; FDA calls the safety database limited.
- **Silent harm 1/3:** Hypersensitivity can arrive months into use but is obvious when it does; injection-site reactions are immediate.
- **Product 3/3:** Users inject grey-market research vials, mostly from China, at large milligram doses that amplify any endotoxin.
- **Never if:** Previous hypersensitivity to elamipretide (label: do not rechallenge); Pregnancy or breastfeeding (no human reproductive data)

## Top reports

- Glowing, energy, 500 mcg titrated to 30 mg: “SS-31 has been the most effective treatment I have tried for improving energy. It has improved my cognitive function by 50%. I can now do moderate cognitive work for 5-10 hrs/week when before I could do none” — [@SplendidSpeseia on X](https://x.com/SplendidSpeseia/status/1896673126869828055)
- Glowing, energy, 5 mg/day: “March 28th of this year I started this cellular mitochondial protocol, and April 10th I regained the feeling in my right foot (mostly). A complete miracle. I can wiggle my toes in bed and feel them now. Ten years later!” — [r/Biohackers](https://www.reddit.com/r/Biohackers/comments/1svq24x/ss31_protocol/opnbpdn/)
- Glowing, energy: “SS-31 is the most life changing thing I‘ve ever taken and I‘ve tried just about everything... Normally my sleep latency is like 10 seconds. I‘m so tired in the evening I have no mental energy for anything. Now I still have the same energy at 9pm as I do at 5am” — [@Fawky on X](https://x.com/Fawky/status/2027784049419555215)
- Glowing, energy, 2-4 mg/day: “They clearly worked synergistically and no I’m not trolling, I’m not a bot, and I’m not kidding - my 4.5 years of long covid (about 75%) and anosmia/parosmia (95%) resolved overnight.” — [r/covidlonghaulers](https://www.reddit.com/r/covidlonghaulers/comments/1og9lw8/ss31_peptide/nutjh0i/)
- Glowing, energy: “I had a mitochondria test and it showed my mitochondria being dysfunctional. SS-31 then MOTSC has changed my life daily energy etc. I was chronically tired even with t levels over 760 and on GH getting great sleep. SS31 fixed the problem Mots-c revved it up higher.” — [@EMoneyMoves on X](https://x.com/EMoneyMoves/status/2002423631222358221)

## Cheapest in Europe

- [Semax Polska](https://semaxpolska.com/en/ss-31-50-mg-woda-bakteriostatyczna/) (PL): SS-31 50 mg + bacteriostatic water, €118, €2.37/mg
- [Baltic Peptides](https://balticpeptides.com/product/ss-31/) (LT): SS-31 (Elamipretide) 50mg, €140, €2.80/mg
- [XL Peptides](https://xlpeptides.com/product/ss-31-10mg/) (GB): SS-31 10mg Research Peptide, €32, €3.23/mg
- [Particle Peptides](https://particlepeptides.com/en/buy-peptides/92-ss-31-50mg.html) (SK): SS-31 50mg, €190, €3.80/mg
- [Europa-Peptide](https://europa-peptide.de/en/shop/ss-31/) (PL): SS-31 50mg, €198, €3.96/mg

## Studies

- [TAZPOWER: elamipretide in Barth syndrome, randomized crossover plus open-label extension (Genet Med 2021)](https://pmc.ncbi.nlm.nih.gov/articles/PMC7935714/) (rct, n=12, 2021): No benefit over placebo in the 12-week crossover; 6-minute walk and fatigue improved over 36 weeks open-label.
- [MMPOWER-2: randomized crossover trial of elamipretide in primary mitochondrial myopathy (J Cachexia Sarcopenia Muscle 2020)](https://pmc.ncbi.nlm.nih.gov/articles/PMC7432581/) (rct, n=30, 2020): 4 weeks of 40 mg/day missed the 6-minute-walk endpoint but improved patient-reported fatigue.
- [MMPOWER-3: efficacy and safety of elamipretide in primary mitochondrial myopathy (Neurology 2023)](https://pmc.ncbi.nlm.nih.gov/articles/PMC10382259/) (rct, n=218, 2023): 24 weeks of 40 mg/day did not improve walking distance or fatigue scores; well tolerated apart from injection-site reactions.
- [ReCLAIM-2: elamipretide in dry AMD with geographic atrophy (Ophthalmol Sci 2024)](https://pmc.ncbi.nlm.nih.gov/articles/PMC11599447/) (rct, n=176, 2024): Missed its low-light visual acuity and atrophy-growth endpoints; slower ellipsoid-zone loss in a secondary analysis.
- [PROGRESS-HF: elamipretide on left ventricular function in HFrEF (J Card Fail 2020)](https://pubmed.ncbi.nlm.nih.gov/32068002/) (rct, n=71, 2020): 4 weeks of daily subQ dosing did not change left ventricular volumes or function.
- [EMBRACE STEMI: IV elamipretide for reperfusion injury in heart attack (Eur Heart J 2016)](https://pubmed.ncbi.nlm.nih.gov/26586786/) (rct, n=118, 2016): No reduction in infarct size versus placebo; no safety signal.

## Sources

- [FDA grants accelerated approval to Forzinity (elamipretide) for Barth syndrome, 19 Sept 2025](https://www.fda.gov/news-events/press-announcements/fda-grants-accelerated-approval-first-treatment-barth-syndrome)
- [Forzinity prescribing information](https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/215244s000lbl.pdf)
- [r/Biohackers: SS-31 protocol thread](https://www.reddit.com/r/Biohackers/comments/1svq24x/ss31_protocol/)