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Semax

A synthetic peptide analog of ACTH(4-10) developed in Russia, studied for cognitive enhancement and neuroprotection.

EmergingModerate Data Beginner-Friendly

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This information is for educational purposes. Peptide therapy should be guided by a licensed healthcare provider. Connect with a Noho clinician

What is Semax?

Semax is a synthetic peptide derived from adrenocorticotropic hormone (ACTH). It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences and has been approved in Russia as a prescription medication for cognitive and neurological conditions. It is primarily discussed for its potential nootropic (cognitive-enhancing) and neuroprotective properties.

Why People Talk About It

Cognitive enhancement and focus

Emerging

Neuroprotection

Emerging

Mood support

Preliminary

Stroke recovery support

Emerging

How It Works

Semax works by increasing levels of brain-derived neurotrophic factor (BDNF), a protein that supports the growth and survival of brain cells. Think of BDNF as fertilizer for your brain — more of it may support better cognitive function, memory, and neural resilience.

Common Questions

Safety Information

Important Safety Notes

Common Side Effects

Nasal irritation (intranasal form)Mild headacheTemporary hair shedding (rare)

Cautions

  • Not FDA-approved in the US
  • Most clinical data from Russian studies
  • Should not be used by those with certain hormonal conditions

What We Don't Know

Western clinical trial data is limited. Long-term cognitive effects and optimal duration of use require further study.

Published Research

31 studies

[The study of chronic partial denervation and quality of life in patients with motor neuron disease treated with semax]

Randomized Controlled TrialPMID: 18379501

[Effectiveness of semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study)]

Clinical TrialPMID: 11517472

The efficacy of semax in the treatment of patients at different stages of ischemic stroke

Clinical TrialPMID: 29798983

Evaluation of therapeutic effect of new Russian drug semax in optic nerve disease

Clinical TrialPMID: 10741256

[Neonatal Semax and saline injections induce open-field behavior changes in mice of different genotypes]

Comparative StudyPMID: 15658043

Comparative study of modulatory effects of Semax and primary proline-containing peptides on hemostatic reactions

Comparative StudyPMID: 11687836

[A nootropic adrenocorticotropin analog 4-10-semax (l5 years experience in its design and study)]

Comparative StudyPMID: 9173745

Comparison of anticoagulant effects of regulatory proline-containing oligopeptides

ReviewPMID: 16634437

Semax peptide targets the μ opioid receptor gene Oprm1 to promote deubiquitination and functional recovery after spinal cord injury in female mice

PreclinicalPMID: 40692165

The Potential of the Peptide Drug Semax and Its Derivative for Correcting Pathological Impairments in the Animal Model of Alzheimer's Disease

PreclinicalPMID: 41479572

Semax, a Copper Chelator Peptide, Decreases the Cu(II)-Catalyzed ROS Production and Cytotoxicity of aβ by Metal Ion Stripping and Redox Silencing

PreclinicalPMID: 40496623

The Effect of Peptide Semax, an ACTH(4-10) Analogue, on Intracellular Calcium Dynamics in Rat Brain Neurons

PreclinicalPMID: 41171324

Antidepressant-like and antistress effects of the ACTH(4-10) synthetic analogs Semax and Melanotan II on male rats in a model of chronic unpredictable stress

PreclinicalPMID: 39442746

Semax, a Synthetic Regulatory Peptide, Affects Copper-Induced Abeta Aggregation and Amyloid Formation in Artificial Membrane Models

PreclinicalPMID: 35080861

Semax, synthetic ACTH(4-10) analogue, attenuates behavioural and neurochemical alterations following early-life fluvoxamine exposure in white rats

PreclinicalPMID: 33418449

[The Peptide Drug ACTH(4-7)PGP (Semax) Suppresses mRNA Transcripts Encoding Proinflammatory Mediators Induced by Reversible Ischemia of the Rat Brain]

PreclinicalPMID: 34097675

Morphofunctional State of the Large Intestine in Rats under Conditions of Restraint Stress and Administration of Peptide ACTH((4-7))-PGP (Semax)

PreclinicalPMID: 33459919

Brain Protein Expression Profile Confirms the Protective Effect of the ACTH((4-7))PGP Peptide (Semax) in a Rat Model of Cerebral Ischemia-Reperfusion

PreclinicalPMID: 34201112

Functional Connectomic Approach to Studying Selank and Semax Effects

PreclinicalPMID: 32342318

Novel Insights into the Protective Properties of ACTH((4-7))PGP (Semax) Peptide at the Transcriptome Level Following Cerebral Ischaemia-Reperfusion in Rats

PreclinicalPMID: 32580520

Composition of Colon Microbiota in Rats Treated with ACTH(4-7)-PGP Peptide (Semax) under Conditions of Restraint Stress

PreclinicalPMID: 32737723

Peptide ACTH(4-7)-PGP: Effects on Various Types of Pain and Pain-Induced Behavior in Rats after Systemic and Central Administration

PreclinicalPMID: 33263853

Experimental Substantiation of Application of Semax as a Modulator of Immune Reaction on the Model of "Social" Stress

PreclinicalPMID: 31028579

Effects of Semax on the Default Mode Network of the Brain

PreclinicalPMID: 30225715

Modulation of GABA- and Glycine-Activated Ionic Currents with Semax in Isolated Cerebral Neurons

PreclinicalPMID: 29577196

Semax, an analog of ACTH((4-7)), regulates expression of immune response genes during ischemic brain injury in rats

PreclinicalPMID: 28255762

Peptides semax and selank affect the behavior of rats with 6-OHDA induced PD-like parkinsonism

PreclinicalPMID: 28702721

Influence of the N-terminus acetylation of Semax, a synthetic analog of ACTH(4-10), on copper(II) and zinc(II) coordination and biological properties

PreclinicalPMID: 27586814

Semax prevents learning and memory inhibition by heavy metals

PreclinicalPMID: 27411820

Semax, an ACTH4-10 peptide analog with high affinity for copper(II) ion and protective ability against metal induced cell toxicity

PreclinicalPMID: 25310602

Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents

PreclinicalPMID: 16362768

Always consult a qualified clinician

This information is for educational purposes. Peptide therapy should be guided by a licensed healthcare provider. Connect with a Noho clinician

Research Insights

Related Peptides

Quick Facts

Class
Nootropic Peptide
Evidence
Emerging
Safety
Moderate Data
Updated
Jan 2026
Citations
31PubMed

Also known as

ACTH(4-7)-PGPSemax Nasal

Tags

Cognitive SupportNeuroprotectionFocusMood

Evidence Score

Overall Confidence55%

Clinical Trials

View Clinical Trials

Links to ClinicalTrials.gov for reference. Listing does not imply endorsement.

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