Head to head

NAD+ vs SS-31

Other

Two compounds that are more often stacked than compared — the side-by-side data, and what actually separates them.

Verdict

Not an either/or

NAD+ and SS-31 appear in each other's stacks in this dataset, so the most common real-world use is together rather than instead of. If you do have to pick one, let route and schedule decide it — NAD+ is subcutaneous, intramuscular, three times a week; SS-31 is subcutaneous, once daily — because the evidence does not separate them cleanly enough to do it for you.

What you are actually choosing between

Before anything else: the dataset lists NAD+ and SS-31 in each other's stacks. They are run together more often than they are chosen between, so if you came here for a winner, the first honest answer is that this may not be an either/or.

Both fall into the catch-all "other" class here, which is a bucket rather than a shared mechanism — NAD+ and SS-31 do not work the same way. What links them is the goal they are reached for, not the biology.

The overlap is longevity and metabolic health. On this site's goal weighting — an editorial priority score, not a measure of effect size — NAD+ rates 4/5 for longevity and SS-31 rates 4/5. Outside that overlap only NAD+ goes further, carrying weight for focus and cognition; SS-31's declared goals stop at the overlap.

The evidence

SS-31 sits one step firmer: controlled human trials behind it, without an approval — results across the trial program have been mixed. NAD+ has some human data, but it is small, old, or uncontrolled — controlled trials studied oral precursors, not injected NAD+. One tier is a real difference but not a decisive one; it should not on its own settle the choice.

How they differ in practice

NAD+ is a subcutaneous injection and an intramuscular injection; SS-31 is a subcutaneous injection. Both are injected, so route does not decide this one.

SS-31 has a characterized half-life of 2.5 h; NAD+ does not have one published here at all. That asymmetry is worth more than it looks — it usually tracks how much formal pharmacology has been done on a compound.

Committed time differs: NAD+ runs 4 weeks, SS-31 runs 8 weeks.

Risk and difficulty

NAD+ is rated intermediate here and SS-31 advanced. That rating is about how much can go wrong in handling, dosing and monitoring, not about how well either works.

Source notes

What the evidence actually says

Verbatim, so you can check the verdict above against what it was built from.

NAD+

A coenzyme, not a peptide. Human evidence for injected NAD+ itself is weak: most controlled trials study oral precursors (nicotinamide riboside, NMN) rather than parenteral NAD+, and the anti-ageing claims attached to it outrun the data. Doses here are large — the range is 25-250 mg with 100 mg typical, so the microgram figures are in the tens and hundreds of thousands (100 mg = 100,000 mcg). NAD+ is also very commonly given intravenously at 250-1000 mg per infusion over 1-4 hours; there is no IV route in this dataset, so subq is listed and IV is noted here instead. IV dosing is not interchangeable with the subq figures above. Subcutaneous administration is notoriously stinging; users typically start at the low end, inject slowly, and dose every other day rather than daily. Circulating NAD+ is cleared and metabolised rapidly, so no meaningful half-life is listed.

SS-31 (Elamipretide)

A mitochondria-targeting tetrapeptide that binds cardiolipin on the inner mitochondrial membrane. Unlike most research peptides it has a real human trial record: Stealth BioTherapeutics has run randomized phase 2 and phase 3 studies in primary mitochondrial myopathy (the MMPOWER program), Barth syndrome, dry age-related macular degeneration and heart failure, most using 40 mg subcutaneously once daily. Results have been mixed — several trials, including MMPOWER-3, missed their primary endpoints — and it is not an approved medicine. The 40 mg upper bound is the trial dose; community protocols typically run far lower at 5-10 mg daily, which is the typical value shown. Plasma half-life after subcutaneous dosing is short, roughly 2-3 hours.

Side by side

The numbers

NAD+ compared with SS-31
Attribute	NAD+	SS-31
Class	Other	Other
Routes	Subcutaneous, Intramuscular	Subcutaneous
Dose range	25 mg–250 mg (typical 100 mg)	5 mg–40 mg (typical 10 mg)
Frequency	Three times a week	Once daily
Half-life	Not characterized	2.5 h
Cycle length	4 weeks	8 weeks
Experience	Intermediate	Advanced
Evidence	Limited human data	Controlled human trials
Contraindications	Pregnant / nursing Under 18	Pregnant / nursing Under 18
Side effects	Marked burning or stinging at the injection site, the most common complaint Flushing, chest tightness or nausea if given too quickly Cramping and a wave of anxiety or restlessness during administration Headache Fatigue for a few hours afterwards	Injection site reactions — redness, itching and induration are common and are the dominant adverse effect reported in trials Headache Nausea Dizziness

Turn a typical dose into a mark on the syringe: NAD+SS-31

Goals

Where they overlap, and where they do not

Goal	NAD+	SS-31
longevity	NAD+: 4/5	SS-31: 4/5
metabolic health	NAD+: 3/5	SS-31: 3/5
neuroprotection	NAD+: 2/5	SS-31: 3/5
recovery and sleep	NAD+: 2/5	SS-31: 3/5
focus and cognitionone only	NAD+: 3/5	SS-31: —
inflammationone only	NAD+: —	SS-31: 2/5

They overlap on 4 goals and diverge on 2. Weights are this site’s editorial priority score out of 5 — how central a goal is to why people use a compound. They are not effect sizes and two 5s do not mean two equal results.

Go deeper

MonographNAD+Mechanism, protocol, storage, sources.MonographSS-31 (Elamipretide)Mechanism, protocol, storage, sources.ToolReconstitution calculatorTurn either dose above into a mark on the syringe.

Other comparisons with these two

Educational information only, not medical advice. Talk to a licensed clinician before starting, changing, or stopping anything.