Head to head
Selank vs Sermorelin
Side-by-side on recovery and sleep, dosing, kinetics and evidence — with an honest verdict at the end.
Verdict
Route decides this one, not potency
What you are actually choosing between
These sit in different classes. Selank is a nootropic; Sermorelin is a growth hormone secretagogue. They get compared because of where they overlap, not because they are interchangeable.
The overlap is recovery and sleep. On this site's goal weighting — an editorial priority score, not a measure of effect size — Selank rates 4/5 for recovery and sleep and Sermorelin rates 4/5. Outside that overlap they diverge: Selank also carries weight for focus and cognition, Sermorelin for longevity and muscle growth.
The evidence
Neither has an evidence edge — both sit at the same tier. Selank: approval from a regulator somewhere, though not a current FDA or EMA label; a registered Russian medicine; the trials are small and Russian-language. Sermorelin: approval from a regulator somewhere, though not a current FDA or EMA label; it was FDA approved as Geref, then withdrawn for commercial reasons. Anyone telling you one is clearly better supported than the other is going beyond what is published.
How they differ in practice
Selank is a nasal spray and a subcutaneous injection; Sermorelin is a subcutaneous injection. That is the difference most people actually feel: Sermorelin means reconstituting a vial and injecting; Selank does not require either. If needles are the deciding factor, this line settles it before any of the rest matters.
Sermorelin has a characterized half-life of 12 min; Selank 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: Selank runs 2 weeks, Sermorelin runs 12 weeks.
Risk and difficulty
The contraindication lists are not the same: Sermorelin flags active malignancy, which Selank does not. If any of those describe you they remove a compound from consideration outright, regardless of everything above.
Sermorelin is rated beginner here and Selank intermediate. 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.
Selank
A synthetic heptapeptide analogue of the immune peptide tuftsin, again with a Pro-Gly-Pro tail added for stability. Its character is anxiolytic rather than stimulant, which is why it is usually paired with, not substituted for, Semax. Like Semax it is a Russian-registered intranasal medicine (commonly a 0.15% solution) and is NOT approved in the US or EU; the human evidence is small Russian trials in generalised anxiety disorder and adjustment disorder, some comparing it against benzodiazepines such as phenazepam, and it has not been independently replicated in Western trials. Route matters: it is an intranasal drug, not an injectable. Russian clinical dosing runs to roughly 1800-2700 mcg per day divided across two or three administrations; the per-dose range here reflects the more conservative doses typical of non-clinical use rather than the full trial daily total. Plasma half-life is minutes, so no hourly figure is listed. Courses are conventionally short (10-14 days) rather than continuous.
Sermorelin
Synthetic analogue of the first 29 amino acids of GHRH. Previously approved in the US as Geref for paediatric GH deficiency and used as a diagnostic agent, then withdrawn from the market for commercial reasons. Because it works through the pituitary it preserves pulsatile GH release, but modern adult data is thin and most anti-ageing dosing is extrapolated from that older clinical use.
Side by side
The numbers
| Attribute | Selank | Sermorelin |
|---|---|---|
| Class | Nootropic | GH secretagogue |
| Routes | Intranasal, Subcutaneous | Subcutaneous |
| Dose range | 150 mcg–900 mcg (typical 300 mcg) | 100 mcg–1 mg (typical 300 mcg) |
| Frequency | Twice daily | Once daily |
| Half-life | Not characterized | 12 min |
| Cycle length | 2 weeks | 12 weeks |
| Experience | Intermediate | Beginner |
| Evidence | Approved elsewhere | Approved elsewhere |
| Contraindications |
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| Side effects |
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Turn a typical dose into a mark on the syringe: SelankSermorelin
Goals
Where they overlap, and where they do not
| Goal | Selank | Sermorelin |
|---|---|---|
| recovery and sleep | Selank: 4/5 | Sermorelin: 4/5 |
| focus and cognitionone only | Selank: 3/5 | Sermorelin: — |
| longevityone only | Selank: — | Sermorelin: 3/5 |
| muscle growthone only | Selank: — | Sermorelin: 3/5 |
| fat lossone only | Selank: — | Sermorelin: 2/5 |
| immune supportone only | Selank: 2/5 | Sermorelin: — |
| injury repairone only | Selank: — | Sermorelin: 2/5 |
| neuroprotectionone only | Selank: 2/5 | Sermorelin: — |
They overlap on 1 goal and diverge on 7. 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.
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Educational information only, not medical advice. Talk to a licensed clinician before starting, changing, or stopping anything.