Semax
ACTH(4-10) Synthetic Analog Heptapeptide
Evidence grade 1 of 5, Untested. Read how the Atlas grades evidence.
Semax is a synthetic ACTH(4-7)PGP heptapeptide built from the ACTH(4-10) fragment and stabilized with a Pro-Gly-Pro tail. Its human evidence base is almost entirely Russian, small (single-country trials reported by Gusev, Skvortsova and colleagues on the order of 30 to 200 acute ischemic stroke patients), and has not been independently replicated by Western groups; there is no Cochrane review, no Western Phase III, and much of the mechanistic weight rests on rat cerebral-ischemia and BDNF/NGF transcription studies. Despite its place on Russia's Vital and Essential Medicines list, the evidence quality is preliminary and unreplicated by international standards, so a grade of 1 is honest.
Counted on the record: 4 human studies, 3 animal studies, 0 lab studies.
The stored Russian-trial totals are not normalized because primary human-study links are incomplete.
- FDA
- Not FDA approved. Not EMA approved. Sold in the West as a research chemical / not for human consumption; included among peptides reviewed by an FDA compounding advisory panel. Registered and marketed in Russia (and Ukraine) since the 1990s.
- WADA
- Not explicitly named on the WADA Prohibited List, but because Semax lacks approval by any Western regulatory health authority it plausibly falls under category S0 (non-approved substances), which bars any pharmacological substance with no current governmental approval for human therapeutic use. Athletes should treat its status as unresolved rather than cleared.
Reference only. Not medical advice.
What can go wrong
Derived from ACTH, the hormone that drives cortisol, so long-term effects on the HPA (stress) axis are uncharacterized; safety data come almost entirely from Russian institutions with no independent Western replication.
Talk to a clinician before taking this. The Atlas can tell you what has been studied about Semax. It cannot tell you how it would interact with your body, your history, or anything else you are taking, and nothing on this page is a reason to start.
A synthetic heptapeptide built from ACTH(4-10), the cognitive-enhancing fragment of the stress hormone ACTH. Developed in 1982 for Soviet military and cosmonaut use. Approved in Russia for stroke and cognitive impairment. Substantial Russian trial data; zero Western RCTs.
Soviet Cold War neuropharmacology. Designed for cosmonauts. Zero Western clinical trials.
What people take it for
These are the reasons people give for taking it. They are not effects it has been shown to have.
Combinations named above are how people use these compounds together, under names the community gave them. The combinations themselves have not been studied. Evidence for one compound is not evidence for a pair.
How it is supposed to work
Semax is a brain-active peptide derived from a fragment of the hormone ACTH, but engineered to drop the hormonal (cortisol-raising) activity and keep the neurological effects. Its central action is to rapidly raise the brain’s own growth factors, BDNF and NGF, which support the survival, growth and connectivity of neurons, while also nudging dopamine and serotonin signaling. On top of that it is neuroprotective, reducing the excitotoxicity and inflammation that damage brain tissue after events like stroke. Given as a nasal spray, it reaches the brain within minutes.
- Step 1ACTH fragmentSemax comes from an ACTH fragment engineered to keep the brain effects and drop the cortisol activity.
- Step 2BDNF and NGFIt rapidly raises the brain's own growth factors, which support neuron survival and connectivity.
- Step 3Dopamine and serotoninIt nudges dopamine and serotonin signalling.
- Step 4After a strokeIt reduces the excitotoxicity and inflammation that damage brain tissue after events like stroke.
- Step 5Nasal deliveryGiven as a nasal spray it reaches the brain within minutes.
Synthetic heptapeptide, ACTH(4-10) with a Pro-Gly-Pro tail.
- Type
- ACTH(4-10) analog
- Sequence
- Met-Glu-His-Phe-Pro-Gly-Pro
- Raises
- BDNF and NGF
- Route
- Intranasal
- Russia
- Registered drug
- FDA
- Not approved
The Evidence Is Real, And In Russian
Semax occupies an unusual middle ground that the West rarely knows what to do with. Most nootropics are either stimulants or supplements whose evidence is barely better than placebo. Semax is neither: it has more mechanistic evidence than almost any Western-marketed nootropic, particularly its rapid, several-fold upregulation of BDNF, and it is a genuinely registered pharmaceutical in Russia, on the national list of essential drugs, used clinically for stroke recovery and cognitive disorders. The catch is where that evidence lives. Nearly all of the clinical research is Russian-language, produced within a single national tradition, with trial-reporting quality that varies and essentially no replication in large Western randomized trials. So the honest position is not that Semax is fake, and not that it is proven by Western standards, but that it has a real mechanism and a real Russian clinical record that Western medicine has never properly vetted.
How it is taken
Intranasal (3 mL glass dropper bottle)
aqueous nasal drops A patent describes existing Russian Semax nasal drops as 0.1% or 1% peptide in purified water with methylparaben. The patent states that this nasal-drop formulation requires storage below 10 C. This is a patent description, not an independently checked label or a general rule for every Semax preparation. Patent background describing a Russian product; not a US approval or prescribing label.
Intranasal
aqueous nasal spray Semax, an antioxidant, an osmolarity-regulating agent, optional antimicrobial preservative, and water. The patent claims room-temperature stability for the proposed formulation. The Atlas does not have an independently validated shelf-life result for this proposed spray. Proposed patent formulation.
Safety in detail
- We hold Semax safety data from Russian clinical use, where the nasal spray is well tolerated and side effects stay mild and infrequent.
- Russia registers it as a medicine, and material outside Russia is research.
Children and teenagers
In Russia, Semax has been used within pediatric neurology for certain cognitive and attention indications under medical supervision, so unlike most peptides here it has some clinical pediatric history in its home system. Outside that system, however, gray-market use in minors has no Western oversight, no independent safety validation, and the same sourcing risks as any research peptide. Any pediatric use should occur only under qualified medical care, never through self-sourced research material.
What people get wrong
Often saidRussian approval means it is Western-validated
ActuallyRussia's regulatory system is separate. No Western RCT has been run, so reproducibility is unknown.
Often saidIt is just a harmless focus aid
ActuallyIt derives from ACTH, the hormone that drives cortisol. Long-term effects on the stress axis are uncharacterized.
Who profits, and who pushes back
Western research community
All meaningful clinical data is Russian. Western researchers cannot evaluate reproducibility without independent trials.
Endocrinology literature
Semax derives from ACTH, which regulates cortisol. Chronic use could affect the HPA axis; long-term human data does not exist.
Tim Ferriss
Discussed across episodes as nootropic experimentation. No supplier relationship identified.
r/nootropics community
One of the largest unincentivized community discussion bases of any cognitive peptide.
Andrew Huberman
Brief mention in comprehensive peptide coverage. No Semax-specific sponsorship.
Semax is a registered pharmaceutical in Russia, manufactured and sold there by Russian drug companies, so unlike a pure gray-market peptide it has a legitimate commercial base in its home market. Outside Russia, the money is the familiar gray-market and nootropic-community economy: research-peptide vendors and nasal-spray sellers serving biohackers and cognitive-enhancement users. Its dual identity, an approved drug at home and a research chemical abroad, shapes both its supply and its perception.
Where the research comes from
Most of the published research on this comes from one place. 88% of it is from Russia. Findings that no unrelated group has reproduced are weaker than the study count makes them look.
| Place | Share of published research |
|---|---|
| Russia | 88% |
| Ukraine | 9% |
| Other | 3% |
Research published from: Russia, Ukraine.
How we got here
Semax is a synthetic heptapeptide analog of the ACTH(4-10) fragment, with a C-terminal Pro-Gly-Pro tail added to resist enzymatic breakdown. It is a registered nootropic and neuroprotective pharmaceutical in Russia, included on the Russian List of Vital and Essential Medicines. Outside Russia it is available only as a research chemical, sold for research use only.
Semax emerged from Soviet and Russian research into ACTH fragments in the early 1980s, developed to create a longer-lasting analog for clinical use. It became a registered Russian pharmaceutical in the early 2000s, used there for stroke recovery and cognitive indications. Since the 2010s it has also circulated internationally as a research chemical, sold strictly for research use only, while remaining untested in Western clinical trials.
Russian clinical development
1997 to 2018
Human stroke studies exist, but their designs fall short of modern confirmatory trials.
- 1997Gusev Stroke StudyThe report associated Semax plus standard care with faster recovery, but its abstract does not describe randomization or blinding.
- 2018Stroke Rehabilitation StudySemax-treated subgroups had higher plasma BDNF and faster improvement in daily-function scores. Allocation was not reported as randomized.
Mechanism research
2006 to 2024
Much of the detailed BDNF and ischemia mechanism remains animal work.
- 2006BDNF Expression StudySemax changed neurotrophin-related expression in rats, supporting a proposed pathway but not proving a clinical mechanism in people.
Origins and adoption
1980s to 2026
Semax moved from a Soviet-era laboratory design to a registered Russian medicine and, more recently, a compounding-review candidate abroad.
- Early 1980sSemax First SynthesizedRussian researchers engineered Semax from the ACTH(4-10) fragment with a stabilizing Pro-Gly-Pro tail.
- 1990s-2000sBDNF Stroke ResearchRussian preclinical and clinical work built the BDNF and stroke-recovery case.
- Early 2000sRussian Drug RegistrationSemax was registered as a pharmaceutical in Russia and added to its essential-drugs list.
- 2010s-2020sInternational Research ChemicalAdopted internationally as a research chemical, sold strictly for research use only, still without Western trials.
- July 2026FDA PCAC VoteFDA PCAC voted 8 to 5, with one abstention, to recommend Semax for the Section 503A bulks list. The advisory vote is not final rulemaking.
The numbers behind the grade
- Type
- ACTH(4-10) analog
- Mechanism
- BDNF/NGF upregulation
- Russia
- Registered drug
- FDA
- Not approved
- Route
- Intranasal
- Western RCTs
- None large
The people taking it
Two groups use it. Russian clinics give it for stroke and cognitive conditions across a broad population, and outside Russia biohackers, students and knowledge workers take it for focus.
One of the two most famous Russian nootropic peptides and a staple of the cognitive-enhancement community, notable for being unusually well grounded in mechanism for a nootropic.
Semax has two distinct user bases. In Russia it is used clinically across a broad population for stroke, cognitive impairment and related conditions, including in pediatric neurology. Abroad it is a nootropic, used by biohackers, students and knowledge workers seeking focus and mental performance, often as the activating half of the Semax-and-Selank stack. As with all gray-market use outside Russia, there is no reliable demographic data on the nootropic users.
Registered and used in Russia for stroke and cognitive disorders, and used worldwide gray-market as a nootropic for focus and neuroprotection. Its standing rests on a real mechanism and a Russian clinical record not replicated in the West.
Set against the alternatives
Against the Western nootropic shelf, Semax stands out for having a defined mechanism and actual drug registration rather than thin supplement evidence. Against its sister peptide Selank, the division is clean and complementary: Semax activates, raising neurotrophins and sharpening cognition, while Selank calms, modulating GABA to reduce anxiety, which is why the two are the most popular nootropic pairing to come out of Russian peptide science. Against a preclinical cognitive peptide like dihexa, Semax has far more human use, if mostly Russian. Its distinction is the combination of real mechanism and real clinical history; its weakness is that the history is unreplicated outside Russia.
What we do not know
- Whether large independent Western trials would replicate the Russian stroke and cognition results.
- Whether the BDNF mechanism produces meaningful real-world cognitive gains in healthy people.
- What its long-term safety profile is by independent evaluation.
- Why, given its mechanism and Russian record, it has not been pursued for Western approval.
What could change
Western neuroprotection interestIts BDNF-driven, anti-excitotoxic profile could attract independent study in stroke and brain injury.Cognitive applicationsWhether it helps healthy cognition remains an open, testable question.Independent trialsThe decisive future step is large Western trials to vet the Russian record.The Semax-Selank stackContinued popularity as the activating half of the Russian nootropic pairing.
Legal status
Semax is a registered pharmaceutical in Russia, on its list of vital and essential drugs, approved there for ischemic stroke, transient ischemic attack, cognitive impairment after head injury, optic-nerve conditions and certain attention and anxiety indications. It is not FDA-approved and is sold in the US and much of the West as a research-use-only compound, commonly as a nasal spray. Its legitimacy depends entirely on jurisdiction.
Status current as of July 2026. Regulatory positions change, sometimes quickly.
The market for this
What follows describes how this is bought and sold. It is not a buying guide and it is not an endorsement of any seller.
In Russia, available as an approved medicine through pharmacies. Abroad, available only as research-use-only material and nasal sprays from peptide and nootropic vendors, which is not an approved medical route; buyers should insist on third-party testing and understand the evidence is Russian and unreplicated.
Inexpensive in Russia as an approved drug, and modestly priced abroad as a research peptide or nasal spray. As with any gray-market product outside Russia, the low cost comes without assurance of identity, dose or purity, so a certificate of analysis matters.
Material comes from Russian pharmaceutical manufacturing for the domestic drug and, for the gray market abroad, from Chinese synthesis sold as research compound. The two differ greatly in oversight, and an independent certificate of analysis is the only check on the latter.
Russia (registered drug)Manufactured and sold as an approved pharmaceutical, the most controlled source.China and research vendorsThe dominant source of gray-market Semax abroad, sold as research-use-only material and nasal sprays.Nootropic-community channelOnline vendors catering to cognitive-enhancement users distribute much of the Western supply.
At a glance
- Sequence
- Met-Glu-His-Phe-Pro-Gly-Pro
- BDNF effect
- 1.4x protein, 3x mRNA (rat)
- Route
- Intranasal
- Russia status
- Essential Drugs List
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Semax.
Nothing outstanding on this one.
Sources
Semax is an analog of ACTH(4-10) that regulates BDNF and trkB expression in the rat hippocampus, supporting a neurotrophic mechanism (animal data).
Semax affects immune- and vascular-system gene expression in rat brain focal ischemia; the strongest ischemia data are animal genome-wide transcriptional studies, not human trials.
Semax and Pro-Gly-Pro activate transcription of neurotrophins and their receptor genes after cerebral ischemia (mechanistic, animal).
Semax is reviewed as a candidate neuroprotective peptide for ischemic stroke, situating it within an experimental (not established) class of stroke drug-discovery agents.
Semax attenuates ischemia-reperfusion injury at the transcriptome level in rats, further evidence the core neuroprotection data are preclinical.
Novel Insights into Protective Properties of ACTH(4-7)PGP (Semax), Genes/MDPI 2020
Semax and Melanotan II, ACTH(4-10) synthetic analogs, show antidepressant-like and antistress effects in male rats under chronic unpredictable stress (animal).
European Journal of Pharmacology (ScienceDirect S0014299924007581)
The FDA convened an advisory panel to evaluate popular peptides for the compounding substances list, confirming several such peptides including nootropic peptides are not FDA-approved drugs and are handled through compounding review.
Drug Topics, FDA Panel to Evaluate 7 Popular Peptides for Compounding Substances List
WADA S0 prohibits any pharmacological substance not addressed elsewhere on the List and with no current approval by any governmental regulatory health authority for human therapeutic use, the framework under which an unapproved peptide like Semax plausibly falls.
Outside Russia, Semax has no regulatory approval, no Western Phase III trials, and no USP monograph, and is sold in the US strictly for research use only; in Russia it is registered and used for stroke and cognitive disorders.
HealingMaps, Semax: The Russian Nootropic Peptide Under FDA Review
Semax is described as a synthetic Met-Glu-His-Phe-Pro-Gly-Pro heptapeptide (ACTH(4-7) core plus Pro-Gly-Pro) used clinically in Russia for ischemic stroke and cognitive impairment.
Peptide Biologix, Semax Molecular Specifications & Research Monograph
The studies that matter
Shadrina; Dolotov et al2001-2006
Showed Semax rapidly increases BDNF and NGF and their signaling in the hippocampus within hours, the core neurotrophic mechanism.
Medvedeva et al, BMC Genomics2014
A genome-wide analysis in a brain-ischemia model found Semax shifts the expression of immune and vascular genes toward protection and recovery.
Russian stroke trials2000s-2010s
Clinical use in ischemic stroke and transient ischemic attack reported reduced deficits and faster recovery versus standard care, the basis for its Russian approval, but not replicated in large Western trials.
Panikratova et al, fMRI2020
A human imaging study directly contrasted Semax and Selank and found distinguishable effects on brain connectivity.
Western randomized trialsnone large
No large independent Western RCT of Semax has been published, so the clinical claims rest on the Russian evidence base.