Peptide Comparison
SemaxvsSelank
A brain-boosting peptide that supercharges your cognitive function by ramping up BDNF—the protein your neurons need to grow, connect, and stay sharp—all delivered through a simple nasal spray.
A clever brain-boosting peptide derived from your immune system's natural tuftsin molecule—it calms anxiety and sharpens your mind without the drowsiness or addiction risks of traditional anti-anxiety medications.
At a Glance
Quick
comparison
Dose Range
Semax
200–900 mcg
Selank
250–500 mcg
Frequency
Semax
Once daily
Selank
Once daily
Administration
Semax
Intranasal spray
Selank
Intranasal
Cycle Length
Semax
4-6 weeks
Selank
4-6 weeks
Onset Speed
Semax
Rapid (hours to days)
Selank
Rapid (hours to days)
Evidence Level
Semax
Moderate human trials (Phase 1-2)
Selank
Limited human trials
Efficacy
Benefit
ratings
Cognitive Enhancement
Neuroprotection
Mental Energy
Anxiety Relief
Immune Support
Technical Data
Compound
specifications
Semax
Molecular Formula
C37H51N9O10S
Molecular Weight
813.9 g/mol
Half-Life
Several minutes to hours (intranasal effects persist longer)
Bioavailability
High via intranasal route (directly reaches brain)
CAS Number
80714-61-0
Selank
Molecular Formula
C33H57N11O9
Molecular Weight
751.9 g/mol
Half-Life
2-3 minutes (plasma); effects last hours due to downstream signaling
Bioavailability
High intranasal absorption; near 100% subcutaneous
CAS Number
129954-34-3
Protocols
Dosing
tiers
Semax
Selank
Applications
Best
suited for
Semax
Students and Knowledge Workers
If your day revolves around learning, studying, or processing complex information, Semax can be a game-changer. It enhances memory consolidation and recall while improving your ability to focus for extended periods—perfect for exam prep or demanding projects.
Those Seeking Mental Clarity
Brain fog? Semax works by boosting BDNF—the protein that helps neurons communicate effectively. Users often report feeling like the 'mental static' clears away, leaving sharper, more efficient thinking in its place.
Neuroprotection Seekers
Beyond immediate cognitive benefits, Semax offers protective effects for your brain cells. It acts as an antioxidant (especially against copper toxicity) and supports neuronal health—valuable for anyone concerned about long-term brain wellness.
Recovery Support (Under Medical Supervision)
In Russia, Semax is approved for helping stroke patients and those with traumatic brain injuries recover cognitive function. While not FDA-approved for this use elsewhere, the research shows meaningful neuroprotective and neurorestorative properties.
Selank
Anxiety Without the Fog
If traditional anti-anxiety medications leave you feeling sedated, foggy, or 'not yourself,' Selank offers a refreshing alternative. It calms anxious thoughts while keeping your mind sharp—like turning down the volume on worry without muting your brain.
Cognitive Performers
Students, professionals, and anyone facing demanding mental tasks love Selank for its dual action. It simultaneously reduces performance anxiety while enhancing memory and focus—the best of both worlds when you need to think clearly under pressure.
Stress Resilience Seekers
Chronic stress wreaks havoc on your brain. Selank helps protect against stress-induced cognitive decline by supporting BDNF levels and modulating your stress response. Think of it as building a buffer between you and life's daily pressures.
Natural Approach Enthusiasts
Derived from tuftsin—a natural peptide your own immune system produces—Selank appeals to those seeking more 'natural' solutions. It works with your body's existing systems rather than overriding them like synthetic drugs.
Safety Profile
Side
effects
Semax
Common
- Nasal irritation
- Mild headache
- Increased alertness
Uncommon
- Temporary blood pressure increase
- Dizziness
Serious
- Allergic reaction
Selank
Common
- Nasal irritation
- Mild fatigue
- Mild headache
- Injection site redness
Uncommon
- Vivid dreams
- Dizziness
Serious
- Allergic reaction
Research Status
Safety
& evidence
Semax
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
Semax has been used clinically in Russia for over 25 years with an excellent safety profile. It's approved there for treating stroke, cognitive impairment, and optic nerve diseases. Studies consistently show minimal side effects, mostly limited to mild nasal irritation when using the spray form. Unlike stimulants, Semax doesn't appear to cause tolerance, dependence, or withdrawal symptoms even with extended use.
Contraindications
- xPregnancy or planning to become pregnant
- xCurrently breastfeeding
- xHistory of seizures or epilepsy
- xKnown allergy to ACTH-related peptides
- xUncontrolled hypertension
Selank
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Selank has demonstrated a favorable safety profile across multiple Russian clinical studies spanning over two decades. In human trials comparing Selank to traditional anxiolytics like phenazepam, Selank showed comparable anti-anxiety effects with significantly better tolerability and no sedation, dependence, or memory impairment. The peptide has been approved for clinical use in Russia since the 1990s for anxiety and neurasthenia.
Contraindications
- xPregnancy or planning to become pregnant
- xCurrently breastfeeding
- xKnown allergy to peptide components
- xChildren and adolescents
- xSevere psychiatric disorders requiring immediate intervention
Decision Guide
Which is
right for you?
Choose Semax if...
- Cognitive enhancement
- Memory improvement
- Focus and concentration
- Neuroprotection
Choose Selank if...
- Anxiety relief without sedation
- Cognitive enhancement and focus
- Memory improvement
- Stress resilience