Brain and sleep peptides

Four of these are registered medicines in Russia: Semax and Selank nose drops, DSIP as Deltaran, and Cerebrolysin, which is also licensed in other countries outside the US. The rest are research compounds with little or no human data, and none is FDA-approved.

Compounds: 9
Approved drug: 4
Human studies: 1
Preclinical: 3
Blends: 1

Members

Semax, Selank and relatives

Semax and Selank are registered in Russia as nose drops; the blend and Adamax are research products built on them, with no studies of their own.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
Semax	Nootropic peptide (ACTH fragment analog)	Approved outside the US	Approved drug	2–4× daily	Not measured	Not banned
Selank	Anxiolytic peptide (tuftsin analog)	Approved outside the US	Approved drug	1–3× daily	a few minutes Label	Not banned
Selank + Semax	Nootropic blend	Blend	Blend	1–2× daily	See each part	Not banned
Adamax	Experimental Semax-derived peptide	Not approved	Preclinical	Once daily	Not measured	Likely banned

Brain extract

A mix of pig-brain peptides given by IV drip or injection, licensed in Russia and other countries outside the US.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
Cerebrolysin	Neurotrophic peptide preparation	Approved outside the US	Approved drug	Once daily during a course	Not measured	Restricted

Research peptides

Not approved anywhere: Dihexa’s injected prodrug failed in Alzheimer’s disease, PE-22-28 has mouse data only, and Pinealon is a Russian bioregulator.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
Dihexa	Angiotensin IV analog (HGF/c-Met modulator)	Not approved	Human studies	Once daily	about 1.5 hours Trial	Likely banned
PE-22-28	TREK-1 potassium-channel blocker (spadin analog)	Not approved	Preclinical	Once daily	Not measured	Likely banned
Pinealon	Short bioregulator peptide	Not approved	Preclinical	Once daily during a course	Not measured	Likely banned

Sleep

Registered in Russia as Deltaran nose drops for stress and alcohol withdrawal, not insomnia; its insomnia trials found weak effects.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
DSIP	Sleep and stress neuropeptide	Approved outside the US	Approved drug	Once nightly	Not measured	Not banned

Approval, evidence, half-life and sport status restate each compound’s own page, where the sources are listed. Select a name for doses, side effects and studies.

How they work

Semax and Selank are seven-amino-acid peptides built from natural fragments: Semax from part of ACTH, a stress hormone, and Selank from tuftsin, a small immune peptide, each with a stabilizing Pro-Gly-Pro tail. Their Russian labels name no target. Semax’s labels call it an ACTH fragment without hormone activity of its own; Selank’s says it eases anxiety through an “original” action on the brain. Label

Laboratory work suggests possible mechanisms. In rats, Semax raised BDNF, a growth factor that helps nerve cells survive and connect, and Selank changed the activity of genes tied to GABA, the brain’s main calming signal. Adamax, sold as a modified Semax, has never been studied. PE-22-28 blocks TREK-1, a potassium channel that acts as a brake on nerve cells, and reduced depression-like behavior in mice within 4 days. Pinealon cut cell-damaging reactive oxygen in cell studies, and Dihexa’s proposed boost to hepatocyte growth factor (HGF), a tissue-growth protein, rests on papers retracted in 2025. Animal

Cerebrolysin is a mix of small peptides from pig brain. Its Russian label says they cross the blood-brain barrier, the brain’s protective filter, act on nerve cells much like natural nerve growth factors, and protect nerve cells from low oxygen. DSIP’s Russian label, for the nasal product Deltaran, says its mechanism is unknown. Label

In people, Cerebrolysin has the largest trials. A 2023 Cochrane review of 7 stroke trials (1,773 people) found no effect on deaths and more non-fatal serious adverse events, while smaller trials in vascular dementia and brain injury favored it. Semax and Selank rest on small Russian studies that compared them with usual care or with benzodiazepines, the sedative anti-anxiety drugs, rather than placebo. DSIP’s insomnia trials found weak effects, and Dihexa’s injected prodrug failed in Alzheimer’s disease. Trial

What they have in common

Russian labels set the limits

Label

Semax’s labels rule out acute psychosis, anxiety disorders, a history of seizures, pregnancy and breastfeeding. Selank’s and DSIP’s rule out pregnancy, breastfeeding and anyone under 18, and DSIP’s advises against a very slow heart rate. Cerebrolysin’s rules out status epilepticus (seizures that don’t stop) and severe kidney failure, and urges caution in epilepsy.

Research powder isn’t the registered drug

Precaution

Only the Russian nose drops (Semax, Selank, Deltaran) and licensed Cerebrolysin solution are regulated products. Powders sold for injection have no regulated standard for identity, purity or sterility, and injecting Semax, Selank or DSIP under the skin has no label or trial basis. The name Adamax covers at least two different molecules.

Small trials

Trial

Semax’s studies had 27–187 people and Selank’s 60–70, mostly published in Russian, with few numbers in the abstracts. No member has a controlled trial of focus or memory in healthy people.

Doubling up

Community

Semax and Selank are often paired, and a premixed 1:1 vial exists; the pair has never been studied. The stack check flags either one taken alongside the blend, since the doses add up, and the blend carries both sets of label cautions.

In sport

Semax, Selank and DSIP are registered in Russia and not named on WADA’s 2026 list, so they aren’t banned. Adamax, Dihexa, PE-22-28 and Pinealon have no approval anywhere and fall under S0, likely banned at all times. Cerebrolysin is allowed except as IV infusions over 100 mL per 12 hours outside hospital care.

How they differ

Status

Registered in Russia: Semax (0.1% and 1% drops), Selank (0.15% drops), DSIP as Deltaran, and Cerebrolysin, which is also licensed in other countries outside the US. None is FDA-approved. Adamax, Dihexa, PE-22-28 and Pinealon aren’t approved anywhere.

Label courses

Label

Semax 0.1%: 2–3 drops per nostril, 2–4 times a day, in courses of 3–14 days. Selank: 2 drops per nostril 3 times a day for 14 days. Deltaran: 300 mcg in the nose 1–3 times a day for 5–10 days. Cerebrolysin: daily IV or IM courses of 10–30 days.

Research compounds

Community

Guides use Dihexa at 5–20 mg by mouth, PE-22-28 at 50–600 mcg injected or sprayed, Adamax at about 100–500 mcg and Pinealon at 1–2 mg, in courses of 10 days to 8 weeks. None of these amounts has been tested in a person.

Targets

Animal

Semax and Selank: unknown, with BDNF and GABA-related changes in rats. Dihexa: HGF signaling, claimed in retracted papers. PE-22-28: the TREK-1 potassium channel, in mice. DSIP: unknown, with no receptor found. Cerebrolysin and Adamax: unknown, since one is a mixture and the other has never been studied.

Human evidence

Trial

Cerebrolysin has placebo-controlled trials with mixed results. Dihexa’s only human data come from its injected prodrug, fosgonimeton, which failed. DSIP has small IV trials from the 1980s to 2009. Semax and Selank have small Russian studies. Adamax, PE-22-28 and Pinealon have no controlled human data.

History

1977Researchers isolate DSIP from rabbits and name it for the slow “delta” brain waves of deep sleep it induced when infused into rabbit brains.
2010French researchers report spadin, the parent peptide of PE-22-28, which blocked TREK-1 and had fast antidepressant-like effects in mice.
2012CASTA, a 1,070-person placebo-controlled trial of Cerebrolysin after stroke, finds no difference on its main 90-day outcome.
2023A Cochrane review of 7 stroke trials (1,773 people) finds Cerebrolysin had no effect on deaths and was linked to more non-fatal serious adverse events.
2025Two papers behind Dihexa’s proposed mechanism are retracted, and the trial of its prodrug in 287 people with Alzheimer’s disease is published, showing no benefit over placebo.

Comparisons and guides

Questions

What are nootropic peptides?

Peptides promoted for focus, memory or mood. The most familiar, Semax and Selank, are registered in Russia as nose drops for stroke, cognition and anxiety. None has a controlled trial for focus or memory in healthy people, and newer research peptides such as Dihexa and PE-22-28 have no tested human dose.

Are Semax and Selank FDA-approved?

No. Both are registered only in Russia, as nose drops: Semax (0.1% and 1%) for cognitive, circulation and stroke uses, Selank (0.15%) for anxiety. In July 2026 FDA’s advisory committee voted to recommend Semax for US pharmacy compounding; Selank wasn’t on the agenda.

Does DSIP help with sleep?

The evidence is weak. Small IV trials in chronic insomnia gave mixed, mostly slight results, and the authors of one double-blind trial judged short-term DSIP unlikely to be of major benefit. Its Russian registration, as Deltaran, covers stress states and alcohol withdrawal, not insomnia.

Has Dihexa been tested in people?

Not as Dihexa. The only human data come from fosgonimeton, an injected prodrug the body turns into the same molecule. It missed its main goals in Alzheimer’s trials, including 287 people in LIFT-AD, and development stopped. The two papers that set out Dihexa’s proposed mechanism were retracted in 2025.

Is Cerebrolysin approved?

Outside the US, yes. It is licensed in Russia and widely used in Eastern Europe and Asia as a solution given by IV drip or injection for stroke, brain injury and dementia. It isn’t FDA-approved, and freeze-dried research vials aren’t the licensed product.

Sources

Semax 0.1% and 1% nasal drops, Russian official instructions (Vidal; registrations of March 26 and June 18, 2025)
Selank 0.15% nasal drops, Russian official instructions (RLS, updated April 8, 2026)
Deltaran (DSIP) powder for nasal solution, Russian official instructions (RLS, updated September 22, 2026)
Cerebrolysin solution for injection, Russian official instructions (RLS, document CERE/RUS/2026/02-3)
Ziganshina et al., Cerebrolysin for acute ischaemic stroke (Cochrane Database Syst Rev 2023) PMID 37818733
Heiss et al., Cerebrolysin in acute ischemic stroke in Asia, CASTA (Stroke 2012) PMID 22282884
Schoenenberger and Monnier, characterization of a delta-sleep-inducing peptide (Proc Natl Acad Sci U S A 1977) PMID 265572
Mazella et al., spadin, a sortilin-derived peptide targeting TREK-1 channels in mice (PLoS Biol 2010) PMID 20405001
Porsteinsson et al., fosgonimeton in mild-to-moderate Alzheimer’s disease, LIFT-AD (J Alzheimers Dis Rep 2025) PMID 41393340
Retraction notice to Benoist et al., the HGF/c-Met mechanism paper for angiotensin IV-derived peptides (J Pharmacol Exp Ther 2025) PMID 40312093

Each compound’s page lists the sources for its own doses, status and studies.

By Vial Guide editorsLast reviewed October 7, 2026

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