Peptide Trainings

Semax vs Selank

Compare two intranasal cognitive and stress-response peptides.

Semax

A nootropic peptide that enhances focus, memory, and neuroprotection

Semax is a synthetic heptapeptide derived from the adrenocorticotropic hormone (ACTH). Developed in Russia, it is one of the most well-studied nootropic peptides and is actually approved as a pharmaceutical drug in Russia for stroke treatment, cognitive enhancement, and neuroprotection. It is widely used in the biohacking community for focus and mental performance.

Mechanism of action

Semax increases BDNF and NGF (Nerve Growth Factor) expression in the brain, promoting neuronal survival and plasticity. It modulates dopaminergic and serotonergic systems, enhances cerebral blood flow, and has anti-inflammatory effects in the CNS. Its ACTH-derived sequence gives it neuroprotective properties without the hormonal effects of full ACTH.

Benefits discussed in research

  • Significantly enhances focus, concentration, and mental clarity
  • Improves memory formation and recall
  • Neuroprotective — reduces damage from stroke and brain injury
  • Increases BDNF (Brain-Derived Neurotrophic Factor)
  • Reduces anxiety and depression symptoms
  • Approved pharmaceutical drug in Russia

Research status

Phase III

Dosing information

For educational and research purposes only. Not medical advice.

typical
200–600 mcg per dose
range
100–1200 mcg per day
frequency
1–2 times daily
route
Intranasal (most common) or subcutaneous injection
cycleLength
2–4 weeks on, 2 weeks off
notes
Intranasal delivery provides rapid onset (within 15–30 minutes). The N-acetyl version (N-Acetyl Semax Amidate) is considered more potent and longer-lasting. Effects include increased mental energy, focus, and verbal fluency.

Side effects and safety

  • Mild stimulation or restlessness at high doses
  • Nasal irritation with intranasal use
  • Headache (rare)
  • Sleep disruption if taken too late in the day

Frequently asked questions

Is Semax a stimulant?

Not in the way caffeine or Adderall are. Those work by forcing your brain to release more dopamine or blocking its reuptake, which is why they cause crashes and dependency. Semax works by helping your brain produce more BDNF — a protein that makes neurons healthier and better connected. The result feels like clarity and focus, not the jittery, wired feeling of a stimulant.

What is the difference between Semax and N-Acetyl Semax Amidate?

N-Acetyl Semax Amidate (often called NASSA) is a chemically modified version of Semax. The modifications make it more resistant to breakdown in the body, so it stays active longer and you need a smaller dose to get the same effect. Most experienced users consider it the upgraded version — more potent, longer-lasting, and better value per dose.

Research references

Read the Semax profile

Selank

A Russian anxiolytic peptide that reduces anxiety without sedation or dependence

Selank is a synthetic heptapeptide developed by the Institute of Molecular Genetics of the Russian Academy of Sciences. It is based on the sequence of tuftsin, an endogenous immunomodulatory peptide. Selank is notable for its anxiolytic (anti-anxiety) effects without the sedation, tolerance, or dependence associated with benzodiazepines.

Mechanism of action

Selank modulates the GABAergic system (similar to benzodiazepines but without receptor downregulation), increases brain-derived neurotrophic factor (BDNF), and modulates serotonin and dopamine levels. It also inhibits the breakdown of enkephalins, which are endogenous opioid peptides that regulate stress and mood. Its immunomodulatory effects come from its tuftsin-derived sequence.

Benefits discussed in research

  • Reduces anxiety and stress without sedation
  • Improves cognitive function, focus, and memory
  • Enhances learning and information processing
  • Stabilizes mood and reduces emotional volatility
  • Immunomodulatory effects — supports immune function
  • No tolerance, dependence, or withdrawal effects

Research status

Phase II

Dosing information

For educational and research purposes only. Not medical advice.

typical
250–500 mcg per dose
range
200–3000 mcg per day
frequency
1–3 times daily
route
Intranasal (most common) or subcutaneous injection
cycleLength
2–4 weeks, can be used as needed
notes
Intranasal administration is the most popular route due to ease of use and good bioavailability. Effects are typically felt within 20–30 minutes. Can be used situationally for acute anxiety or as a daily protocol for chronic stress.

Side effects and safety

  • Mild sedation at high doses
  • Nasal irritation with intranasal use
  • Slight dizziness (rare)
  • Generally very well tolerated

Frequently asked questions

Is Selank like a benzodiazepine?

It reduces anxiety like a benzodiazepine, but that is where the similarity ends. Benzodiazepines (Xanax, Valium, Ativan) work by flooding your GABA system, which causes sedation and creates dependency over time. Selank gently modulates the same system without overwhelming it, which is why it does not cause the foggy feeling, tolerance, or withdrawal that makes benzos so problematic.

Can I take Selank and Semax together?

Yes, and this is actually one of the most popular combinations in the peptide community. Think of it this way: Semax sharpens your focus and mental energy, while Selank takes the edge off anxiety. Together they give you clear, calm focus — the kind that is hard to find with stimulants alone. Both are nasal sprays, so the routine is simple.

Research references

Read the Selank profile

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