Semax is a synthetic ACTH fragment peptide, also called ACTH(4-7)PGP, studied mainly for neurological and cognitive-related conditions. The indexed human evidence is limited but not absent: Chia’s evidence grade is B, based on one randomized trial and several human clinical trials, mostly outside large modern U.S. trial programs 1 2 3 4.
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See if you qualify →What it is
Semax is a synthetic peptide derived from a fragment of adrenocorticotropic hormone, or ACTH. It is also described as ACTH(4-7)PGP and Met-Glu-His-Phe-Pro-Gly-Pro, with Semax used as the compound name in the research records supplied for this page 12.
In plain English, Semax is an ACTH-fragment analogue peptide. That means it resembles part of a natural hormone sequence, but it is not the same as full ACTH and should not be assumed to act like full ACTH in the body 12.
The human literature in this evidence set is mostly neurologic. Studies indexed in PubMed include ischemic stroke, hemispheric ischemic stroke, optic nerve disease, and motor neuron disease with chronic partial denervation and quality-of-life outcomes 1 2 3 4.
This page should be used as an evidence map, not as a treatment plan. If you are comparing Semax with related peptides, Chia’s deeper guides on Semax research, Selank, and N-Acetyl Semax Amidate can help you separate names that sound similar but are not interchangeable.
Mechanism of action
Semax is thought to work through neurochemical and neuroimmune pathways, but its mechanism in humans is not fully established. The most defensible wording is “proposed mechanism,” because much of the mechanistic evidence comes from animal or laboratory-style studies rather than large human trials 7 11 12.
Rodent research described Semax as an ACTH(4-10) analogue with nootropic properties and reported activation of dopaminergic and serotoninergic brain systems in rodents 12. That is animal neurochemistry evidence, not proof that Semax improves focus, mood, or performance in people.
Animal ischemia models have also studied ACTH-like peptides and brain gene-expression profiles after experimental stroke. In those animal studies, researchers reported changes in gene-expression patterns after ischemic injury, but animal ischemia findings cannot be upgraded into a human stroke-benefit claim 7 9.
A functional-connectomic study evaluated Selank and Semax effects using brain-network methods 6. Functional connectomics can be useful for studying brain signaling, but it does not, by itself, prove that a peptide improves a clinical outcome a patient can feel.
Evidence
Semax has a Chia evidence grade of B. That grade reflects the number and design of indexed studies in the supplied PubMed set, not a conclusion that Semax works or that it is safe.
The supplied PubMed set includes one randomized controlled trial involving patients with motor neuron disease, chronic partial denervation, and quality-of-life outcomes 4. It also includes human clinical trials in ischemic stroke, hemispheric ischemic stroke, and optic nerve disease 1 2 3.
That is enough for grade B under this rubric, but it is still a thin evidence base. The studies are older or specialized, the topics are neurologic, and this set does not show large modern U.S. trial programs for general nootropic use, ADHD, or everyday cognitive enhancement 1 2 3 4.
What benefits has Semax been studied for?
In humans, Semax has been studied in ischemic stroke and hemispheric ischemic stroke 1 3. These records support saying Semax has been studied in those settings; they do not support using this article to make an individual stroke-care decision.
Semax has also been evaluated in optic nerve disease in a human clinical trial 2. The citation supports that the topic was studied, but this page should not be read as saying Semax is established care for optic nerve disease.
A randomized controlled trial studied Semax in people with motor neuron disease, chronic partial denervation, and quality-of-life endpoints 4. A single randomized study is important, but it is not the same as a broad, replicated evidence base.
For nootropic claims, the evidence is more indirect. Rodent work reported dopaminergic and serotoninergic effects, and functional-connectomic research has studied Semax-related brain-network effects, but these are not the same as proven improvements in memory, focus, or ADHD symptoms in people 6 12.
| Claim people ask about | What the supplied evidence supports | What it does not prove |
|---|---|---|
| Ischemic stroke | Human clinical trials studied Semax in ischemic stroke settings 1 3. | It does not prove Semax should be self-used for stroke symptoms. |
| Optic nerve disease | A human clinical trial evaluated Semax in optic nerve disease 2. | It does not establish Semax as standard eye or nerve care. |
| Motor neuron disease | One randomized human trial studied Semax in motor neuron disease with chronic partial denervation and quality-of-life outcomes 4. | It does not prove broad benefit across all motor neuron diseases. |
| Nootropic or focus use | Animal and functional-connectomic studies explore brain signaling 6 12. | It does not prove better focus, memory, or productivity in healthy adults. |
| ADHD | The supplied evidence set does not include an ADHD clinical trial. | It does not support an ADHD efficacy claim. |
What studies exist
| Year | Design | Study | Journal | Record |
|---|---|---|---|---|
| 2018 | Clinical trial | [The efficacy of semax in the tretament of patients at different stages of ischemic stroke] | Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova | PMID 29798983 |
| 2000 | Clinical trial | [Evaluation of therapeutic effect of new Russian drug semax in optic nerve disease] | Vestnik oftalmologii | PMID 10741256 |
| 1997 | Clinical trial | [Effectiveness of semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study)] | Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova | PMID 11517472 |
| 2007 | Randomised controlled trial | [The study of chronic partial denervation and quality of life in patients with motor neuron disease treated with semax] | Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova | PMID 18379501 |
| 2020 | Primary study | Functional Connectomic Approach to Studying Selank and Semax Effects | Doklady biological sciences : proceedings of the Academy of Sciences of the USSR, Biological sciences sections | PMID 32342318 |
| 2026 | Review / secondary | Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions | Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews | PMID 41490200 |
| 2024 | Primary study | ACTH-like Peptides Compensate Rat Brain Gene Expression Profile Disrupted by Ischemia a Day After Experimental Stroke | Biomedicines | PMID 39767736 |
| 2017 | Primary study | [A comparative chemoreactome analysis of mexidol] | Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova | PMID 28514338 |
| 2021 | Primary study | The Influence of Selank on the Level of Cytokines Under the Conditions of "Social" Stress | Current reviews in clinical and experimental pharmacology | PMID 32621722 |
| 2020 | Primary study | Correction of Lipid Metabolism Disorders in Diabetes Mellitus with Peptide Drugs | Bulletin of experimental biology and medicine | PMID 32246363 |
| 2018 | Review / secondary | Pharmacological Aspects of Neuro-Immune Interactions | Current pharmaceutical design | PMID 28875850 |
| 2021 | Primary study | A Mouse Model of Nigrostriatal Dopaminergic Axonal Degeneration As a Tool for Testing Neuroprotectors | Acta naturae | PMID 34707903 |
This table is retrieved from PubMed and ClinicalTrials.gov rather than assembled by hand, so it shows what is indexed — including the absences. Last retrieved 2026-09-07.
Reported dosing ranges
Semax dosing should not be inferred from this page. The supplied PubMed citation records identify human studies, but the retrieved records available for drafting do not provide enough route-and-dose detail to build a reliable human dosing chart 1 2 3 4.
That matters because peptide dosing is not just a number. Route, concentration, sterility, diagnosis, other medications, and monitoring all change the risk profile, and self-directed dosing from forums or vendor pages is not a substitute for clinician review 5 11.
| Evidence source | Population or model | Route or dose available from retrieved record | How to interpret it |
|---|---|---|---|
| Gusev et al., 2018 ischemic stroke clinical trial 1 | Human ischemic stroke study | Not available in the retrieved citation record | Shows Semax was studied in this setting; does not provide a dosing recommendation here. |
| Polunin et al., 2000 optic nerve disease clinical trial 2 | Human optic nerve disease study | Not available in the retrieved citation record | Shows Semax was evaluated in this setting; does not provide a dosing recommendation here. |
| Gusev et al., 1997 hemispheric ischemic stroke clinical trial 3 | Human acute hemispheric ischemic stroke study | Not available in the retrieved citation record | Shows Semax was studied in this setting; does not provide a dosing recommendation here. |
| Serdiuk et al., 2007 randomized controlled trial 4 | Human motor neuron disease study | Not available in the retrieved citation record | Shows randomized human study exists; does not provide a dosing recommendation here. |
| Animal and mechanistic studies 7 9 12 | Rodent or other animal models | Not used for patient dosing | Animal dosing should not be converted into human self-use instructions. |
For a deeper discussion of why dosing charts can be misleading when source details are thin, see Chia’s Semax peptide dosage chart. It explains what research can and cannot tell a patient before a licensed clinician reviews the full context.
Legal status
| Date | Action | What it means | Source | Evidence |
|---|---|---|---|---|
| 2026-07-24 | Advisory committee reportedly voted 8-5-1 in favour of including Semax on the 503A bulk drug substances list | Advisory vote only, as reported. FDA has not added it to the list, and the substance is not FDA-approved. | Healio (2026-07-24) | Reported — no agency record |
| 2026-07-23 | FDA convened the Pharmacy Compounding Advisory Committee to consider seven peptide bulk drug substances for the 503A list | The meeting establishes that these substances were formally considered. It does not change any substance's status. | FDA Advisory Committee Calendar | FDA / Federal Register |
This section is generated from a dated log of federal actions rather than written by hand, and it is re-checked daily against the Federal Register and FDA sources. Last checked 2026-09-07. See the full legal-status tracker for every compound we follow.
Safety
Semax safety is not settled by the human trial record. The supplied evidence set shows that human trials exist, but it does not provide a large safety database that can rule out uncommon, delayed, or interaction-related adverse effects 1 2 3 4.
Small or older trials can miss uncommon harms. They may also study narrow groups, such as people with neurologic disease, which may not predict safety in healthy adults using a peptide for focus, energy, or nootropic goals 1 4.
Mechanistic animal findings should not be read as safety reassurance. Rodent studies suggest Semax can affect dopaminergic and serotoninergic systems, and neuroimmune reviews discuss peptide effects in complex signaling networks; that combination is a reason for caution, not casual self-use 11 12.
The biggest practical safety issue is source quality. Products sold as “research use only” are not made for people, and they may raise risks around sterility, identity, impurities, storage, and concentration; modern peptide reviews also note translation and quality challenges for therapeutic peptides 5.
- Speak with a licensed clinician before considering any peptide, especially if you have a neurologic condition, seizure history, psychiatric condition, eye disease, or cardiovascular risk.
- Seek urgent medical care for stroke-like symptoms, sudden vision changes, severe headache, weakness, chest pain, or trouble speaking.
- Avoid using vendor claims, Reddit threads, or group buys as medical evidence; Chia’s guide to finding a legitimate peptide source explains why licensed evaluation and pharmacy standards matter.
Interactions
Semax interactions have not been well defined in the supplied human evidence set. The records provided for this page do not include dedicated human drug-interaction studies, so the honest answer is not “no interactions”; it is “not adequately studied” 1 2 3 4.
Because rodent data suggest effects on dopaminergic and serotoninergic systems, people using antidepressants, stimulants, dopamine-active medications, migraine drugs, seizure medications, or multiple nootropics should not assume Semax is interaction-free 12. This is a question for a clinician who can review the full medication list.
Pregnancy, breastfeeding, and pediatric use are also not answered by this evidence set. The supplied records do not establish safety in those groups, and peptide reviews emphasize that clinical translation requires careful evaluation rather than assumptions from early or specialized studies 5.
| Question to ask a clinician | Why it matters |
|---|---|
| Do I have a neurologic condition that changes the risk? | Most human studies in this set are neurologic, so context matters 1 3 4. |
| Could Semax interact with psychiatric or stimulant medications? | Animal research suggests dopaminergic and serotoninergic effects, but human interaction studies are not established here 12. |
| Is pregnancy, breastfeeding, or pediatric use relevant? | The supplied evidence set does not establish safety for these groups. |
| Is the product from a licensed pharmacy rather than a research-chemical vendor? | Source quality affects sterility, identity, concentration, and impurity risk 5. |
How to obtain it legally
The safe process for any peptide starts with a licensed clinician, a clear medical history, and pharmacy-grade dispensing when a prescription is appropriate. Semax is education-only at Chia: we do not currently offer Semax.
A clinician evaluation should review the reason someone is asking about Semax, neurologic history, mental health history, current prescriptions, supplements, pregnancy or breastfeeding status, and whether there are symptoms that need urgent care instead of peptide use. A prescription, when clinically appropriate, is a medical decision and is never guaranteed.
A licensed pharmacy is different from a research-chemical vendor. Pharmacy dispensing is built around patient use, identity checks, quality systems, and clinician oversight; “research use only” material is not a patient medication and should not be treated like one 5.
At Chia, we do prescribe certain compounded GLP-1 and longevity treatments after an online evaluation, but only for treatments in our live catalog. Semax is not one of them. If your goal is broader peptide education, you may also find our guide to the best peptides for energy useful because it separates human evidence from animal and mechanistic claims.
How does Semax compare with related nootropic peptides?
Semax and Selank are often discussed together, but they should not be treated as interchangeable. A functional-connectomic study looked at Selank and Semax effects, but comparison claims about real-world outcomes exceed what that type of study can prove 6.
N-Acetyl Semax Amidate is also a separate name patients may see online. Similar naming does not prove the same evidence, safety profile, or clinical role; if you are comparing the two, start with Chia’s guide to N-Acetyl Semax Amidate and avoid assuming one peptide’s data transfers to another.
| Peptide or name | What it is | Evidence caution |
|---|---|---|
| Semax | Synthetic ACTH fragment analogue peptide, also called ACTH(4-7)PGP. | Human studies exist, but they are limited and mostly neurologic 1 2 3 4. |
| Selank | A related nootropic/anxiolytic peptide discussed in brain-network research. | Do not assume Selank and Semax have the same effects; see Chia’s Selank guide. |
| N-Acetyl Semax Amidate | A Semax-related derivative name often discussed online. | Do not assume interchangeability without compound-specific evidence. |
Semax has been studied mainly in neurologic settings, including ischemic stroke, optic nerve disease, and motor neuron disease. The evidence does not prove broad nootropic benefits for healthy adults, and it should not be used to make stroke, eye, or neurologic care decisions without a clinician.
Anyone with a neurologic condition, seizure history, major psychiatric condition, pregnancy, breastfeeding, pediatric use, or complex medication list should speak with a licensed clinician before considering Semax. The available evidence does not establish safety for these situations.
The supplied evidence set does not include a clinical trial of Semax for ADHD. Claims about ADHD, stimulation, or focus should be treated as unproven unless supported by human clinical research.
Animal research suggests Semax can affect dopamine and serotonin brain systems, but that does not prove a predictable stimulant effect in humans. People taking stimulants, antidepressants, or other nootropics should not assume it is interaction-free.
No. Semax is a synthetic fragment analogue related to part of the ACTH sequence. It should not be treated as the same thing as full ACTH.
The retrieved citation records identify human Semax studies but do not provide enough dose-and-route detail to create a reliable dosing range here. Any dosing discussion should come from the full published source and a licensed clinician, not from a vendor page or forum.
Research-use products are not patient medications. They may create risks around sterility, identity, concentration, impurities, and lack of clinical oversight.
No. Chia does not currently offer Semax. This page is education-only, written to help patients understand the evidence, risks, and access questions before making decisions with a licensed clinician.
References
- 1.PMID 29798983 [clinical trial] Gusev EI, Martynov MY, Kostenko EV, et al. [The efficacy of semax in the tretament of patients at different stages of ischemic stroke]. Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova. 2018.
- 2.PMID 10741256 [clinical trial] Polunin GS, Nurieva SM, Baiandin DL, et al. [Evaluation of therapeutic effect of new Russian drug semax in optic nerve disease]. Vestnik oftalmologii. 2000.
- 3.PMID 11517472 [clinical trial] Gusev EI, Skvortsova VI, Miasoedov NF, et al. [Effectiveness of semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study)]. Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova. 1997.
- 4.PMID 18379501 [randomised controlled trial] Serdiuk AV, Levitskiĭ GN, Miasoedov NF, et al. [The study of chronic partial denervation and quality of life in patients with motor neuron disease treated with semax]. Zhurnal nevrologii i psikhiatrii imeni S.S. Korsakova. 2007.
- 5.PMID 41490200 [review/secondary] Rahman OF, Lee SJ, Seeds WA. Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions. Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews. 2026.
- 6.PMID 32342318 [primary study] Panikratova YR, Lebedeva IS, Sokolov OY, et al. Functional Connectomic Approach to Studying Selank and Semax Effects. Doklady biological sciences : proceedings of the Academy of Sciences of the USSR, Biological sciences sections. 2020.
- 7.PMID 39767736 [primary study] Filippenkov IB, Shpetko YY, Stavchansky VV, et al. ACTH-like Peptides Compensate Rat Brain Gene Expression Profile Disrupted by Ischemia a Day After Experimental Stroke. Biomedicines. 2024.
- 8.PMID 32246363 [primary study] Elagina AA, Lyashev YD, Lyashev AY, et al. Correction of Lipid Metabolism Disorders in Diabetes Mellitus with Peptide Drugs. Bulletin of experimental biology and medicine. 2020.
- 9.PMID 40650034 [primary study] Filippenkov IB, Shpetko YY, Ales DA, et al. Genes That Associated with Action of ACTH-like Peptides with Neuroprotective Potential in Rat Brain Regions with Different Degrees of Ischemic Damage. International journal of molecular sciences. 2025.
- 10.PMID 41479572 [primary study] Radchenko AI, Kuzubova EV, Apostol AA, et al. The Potential of the Peptide Drug Semax and Its Derivative for Correcting Pathological Impairments in the Animal Model of Alzheimer's Disease. Acta naturae. 2025.
- 11.PMID 28875850 [review/secondary] Tarasov VV, Kudryashov NV, Chubarev VN, et al. Pharmacological Aspects of Neuro-Immune Interactions. Current pharmaceutical design. 2018.
- 12.PMID 16362768 [primary study] Eremin KO, Kudrin VS, Saransaari P, et al. Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents. Neurochemical research. 2005.
About this article
Chia Health Editorial Team — Evidence-reviewed health education
This article is for educational purposes only and is not a substitute for individualized medical advice. Talk to a licensed clinician before starting, stopping, or changing any prescription.
AI tools may assist with research and drafting. Chia's editorial team reviews source use, clarity, treatment information, and safety framing before publication. A clinician is named only after explicit sign-off. Read our editorial standards.
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