Semax
Also known as: NA-Semax
Synthetic ACTH Analog | Nootropic & Neuroprotective Peptide
Overview
Semax is a synthetic heptapeptide derived from adrenocorticotropic hormone (ACTH) fragment 4-10, originally developed in Russia for stroke recovery. It achieves enhanced CNS penetration through direct transport via olfactory epithelium and trigeminal nerves, bypassing the blood-brain barrier.
Key benefits
- Rapid brain delivery via intranasal route
- Rapidly increases BDNF levels
- Extensive clinical research in Russia
- Easy self-administration
- Modulates dopamine and serotonin systems
- Neuroprotective effects
Mechanism of action
Rapidly increases BDNF levels, modulates dopaminergic and serotonergic systems, and achieves direct brain delivery through olfactory transport with 0.093% blood-brain barrier penetration (vs 0.01% IV).
Molecular data
- Type
- ACTH(4-10) synthetic analog
- Half-life
- 0.5-2 hours
Sequence
Met-Glu-His-Phe-Pro-Gly-Pro
Indications
What the research community uses this compound for, with self-reported effectiveness.
Cognitive
Memory Enhancement
Most effectiveImproved short-term and working memory performance in fatigued individuals (71% vs 41% accuracy).
Attention and Focus
Most effectiveEnhanced sustained attention during demanding cognitive tasks.
Learning Acceleration
EffectiveFaster acquisition of new information and improved retention.
Neuroprotection
Stroke Recovery
EffectiveAccelerated rehabilitation with increased BDNF levels in stroke patients.
Brain Trauma Support
EffectiveSupports recovery from traumatic brain injury.
Neurodegenerative Prevention
EffectiveShows anti-amyloid properties in Alzheimer's models.
Neuroplasticity
BDNF Upregulation
ModerateSupports neurogenesis through increased brain-derived neurotrophic factor.
Neural Connectivity
ModerateEnhanced neural connections and brain network activity.
Stress Resilience
ModerateImproved ability to cope with cognitive stress.
Dosing protocols
Common protocols by delivery method. Adjust the curve below to model accumulation in your own cycle.
Nasal
Intranasal is the primary and most effective route, providing direct brain delivery through olfactory transport. Onset 15-30 minutes, peak 1-2 hours, duration 4-6 hours.
| Protocol | Dose | Frequency | Route / duration |
|---|---|---|---|
| Cognitive enhancement | 300-600mcg | 1-2x daily | Intranasal spray/drops |
| Intensive cognitive support | 600-900mcg | 2-3x daily | Intranasal |
| Brain injury recovery | 900-1500mcg | 2-3x daily | Intranasal |
Preparation
You will need
- Semax solution (0.1% or 1%)
- Nasal spray bottle
- Preservative-free saline (if reconstituting)
Steps
- Pre-mixed solutions available as 0.1% or 1%
- For research: reconstitute powder with sterile saline
- Use preservative-free saline for nasal administration
- Calculate concentration per spray/drop desired
- Refrigerate and use within recommended timeframe
- Alternate nostrils when administering
Work out the water volume and syringe units in the reconstitution calculator →
Injectable
Subcutaneous injection provides reliable dosing. Onset 30-60 minutes, peak 2-4 hours, duration 6-8 hours.
| Protocol | Dose | Frequency | Route / duration |
|---|---|---|---|
| Research protocol | 500-750mcg | 1x daily | SubQ |
| Intensive protocol | 750-1000mcg | 1-2x daily | SubQ |
Preparation
You will need
- Semax lyophilized powder
- Bacteriostatic water
- Insulin syringes (25-27 gauge)
- Alcohol swabs
Steps
- Allow vial to reach room temperature
- Clean vial tops with alcohol
- Inject water slowly down the side of the vial to avoid foaming
- Gently swirl until completely dissolved
- Draw into syringe using appropriate gauge needle
- Refrigerate reconstituted solution
Work out the water volume and syringe units in the reconstitution calculator →
Interactions
Pairwise interactions with other compounds you might be cycling — the same data behind the cycle builder's safety check.
NA-Semax-Amidate
AvoidDo NOT use simultaneously. Choose one or the other - they are variants of the same peptide.
Stimulants
MonitorMay enhance stimulant effects - monitor carefully and reduce stimulant doses.
MAO Inhibitors
MonitorTheoretical monoamine system risk; use caution.
Selank
SynergisticComplementary anxiolytic effects; popular combination.
BPC-157
CompatibleBoth support neuroplasticity through different mechanisms.
TB-500
CompatibleComprehensive neuroprotection when combined.
Timeline
Typical week-by-week effects reported in clinical and observational data.
- Days 1-3
Initial cognitive clarity and focus enhancement, possible mild nasal sensation
- Week 1
Improved attention span during demanding tasks
- Week 2-3
Enhanced memory consolidation, stable mood
- Week 4
Peak cognitive benefits with improved stress resilience and mental flexibility
- Post-cycle
Gradual baseline return over 3-7 days; some benefits persist
Safety
Reported adverse effects, contraindications, and what to monitor on cycle.
Common side effects
- Mild nasal discomfort (nasal route)
- Possible nasal sensation upon administration
Stop signs — stop and seek advice
- Severe nasal irritation, bleeding, or persistent congestion
- Unusual anxiety, agitation, or sleep disturbances
- Headaches worsening with use
- Signs of allergic reaction (rash, breathing difficulty)
- Significant blood pressure changes or heart palpitations
Contraindications
- Pregnancy or breastfeeding
- Known peptide allergies
- Do not exceed 4-week continuous use without medical supervision
Monitoring
- Start with lowest effective dose (300mcg) to assess individual response
- Avoid concurrent intranasal vasoconstrictors
- Monitor for nasal irritation/bleeding
- May enhance stimulant effects - reduce other stimulant doses
Quality checks
What a legitimate product looks like, what should give pause, and what should make you stop.
Good signs
- Clear, colorless solution (nasal)
- Proper concentration labeling as 0.1% or 1% Semax
- Cold chain shipping with cold packs
- Sterile packaging (sealed bottles/ampoules)
- White lyophilized powder (injectable)
- Complete dissolution in solution
- Third-party testing (≥98% purity)
Warning signs
- Nasal irritation potential
- Injection site reactions (redness, swelling)
Stop signs — don't use
- Crystallization or precipitation indicates degradation
- Cloudy or colored solutions
- Any visible particles
Recent research
Newer papers and trial readouts on file for this compound, with source and date.
2025 · International Journal of Molecular Sciences
The Potential of the Peptide Drug Semax and Its Derivative for Correcting Pathological Impairments in the Animal Model of Alzheimer's Disease
Semax and its derivative improved cognitive functions in transgenic Alzheimer's mice; amyloid plaque count decreased 2.8-fold in the Semax group versus untreated controls.
2022 · ACS Chemical Neuroscience
Semax, a Synthetic Regulatory Peptide, Affects Copper-Induced Abeta Aggregation and Amyloid Formation in Artificial Membrane Models
Semax prevents formation of Abeta:Cu2+ complexes and inhibits amyloid fiber formation, demonstrating anti-aggregating and neuroprotective properties relevant to Alzheimer's disease.
2025 · British Journal of Pharmacology
Semax Peptide Targets the Mu Opioid Receptor Gene Oprm1 to Promote Functional Recovery After Spinal Cord Injury
Semax improved spinal cord injury functional recovery and inhibited pyroptosis in mice by targeting mu-opioid receptors and regulating the USP18 deubiquitination pathway.
2025 · Bioinorganic Chemistry and Applications
Semax, a Copper Chelator Peptide, Decreases Cu(II)-Catalyzed ROS Production and Cytotoxicity of Abeta
Semax extracts Cu(II) from Cu(II)-amyloid-beta species and decreases associated ROS production, showing cytoprotective properties against copper-mediated oxidative stress.
References
Primary literature and clinical-trial data informing this entry.
A Nootropic Adrenocorticotropin Analog 4-10 Semax: 15 Years Experience in Its Design and Study
Ashmarin IP, Nezavibatko VN, Levitskaya NG, et al. · Zhurnal Vysshei Nervnoi Deiatelnosti imeni I.P. Pavlova · 1997
Foundational 15-year review: Semax stimulates operative memory and attention, increases hypoxia resistance, and improves brain circulation for 20-24 hours after intranasal doses of 0.015-0.050 mg/kg.
The Efficacy of Semax in the Treatment of Patients at Different Stages of Ischemic Stroke
Gusev EI, Barskov IV, et al. · Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova · 2018
110 patients after ischemic stroke; Semax (6000 mcg/day intranasal) increased BDNF plasma levels, sped functional recovery, and improved motor performance during rehabilitation.
Effects of Semax on the Default Mode Network of the Brain
Dolgorukova AM, Klyushnik TP, Gusev EI, et al. · Bulletin of Experimental Biology and Medicine · 2018
24 healthy volunteers (43.9 +/- 9.5 years); resting-state fMRI showed increased default mode network volume in medial frontal cortex after intranasal 1% Semax vs placebo.
The Peptide Semax Affects the Expression of Genes Related to the Immune and Vascular Systems in Rat Brain Focal Ischemia: Genome-Wide Transcriptional Analysis
Dergunova LV, Limborska SA, et al. · BMC Genomics · 2014
Genome-wide study of ischemized rat brain cortex: Semax modulated expression of 24 vascular genes at 3h and enhanced immune-response gene expression at 24h post-pMCAO, including immunoglobulin and chemokine groups.
Semax, an Analog of ACTH(4-10) with Cognitive Effects, Regulates BDNF and trkB Expression in the Rat Hippocampus
Dolotov OV, Karpenko EA, Inozemtseva LS, et al. · Brain Research · 2006
Single application at 50 mcg/kg produced 1.4-fold increase in BDNF protein and 1.6-fold increase in trkB tyrosine phosphorylation in rat hippocampus.
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