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ToolsComparePentapeptide-18 vs Selank

Pentapeptide-18 vs Selank

Side-by-side comparison of key properties, dosing, and research.

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Cognitive Enhancement
Selank
Summary
Pentapeptide-18 (Leuphasyl) is a synthetic pentapeptide that mimics the sequence of enkephalin, an endogenous neuropeptide. It acts on neuronal pain receptors in facial muscles to reduce muscle contraction intensity and depth of expression lines, functioning similarly to Argireline (Acetyl Hexapeptide-3) but via a different receptor mechanism.
Selank is a synthetic heptapeptide analog of tuftsin developed in Russia. It is a potent anxiolytic that reduces anxiety and enhances cognitive function without sedation or addiction. It is approved for clinical use in Russia for anxiety disorders.
Half-Life
Not applicable (topical)
Minutes (but effects persist for hours)
Admin Route
Topical
SubQ, Intranasal
Research
Typical Dose
0.005–0.05% in formulation
250–500 mcg
Frequency
Twice daily
1–3 times daily
Key Benefits
  • Reduces depth of expression lines (forehead, crow's feet, glabellar)
  • Inhibits acetylcholine release for muscle-relaxing effect
  • Complementary mechanism to Argireline for enhanced anti-wrinkle activity
  • Reversible and well-tolerated
  • No risk of systemic paralysis at cosmetic concentrations
  • Suitable for daily use in serums and creams
  • Reduces anxiety without sedation
  • Enhances memory and learning
  • Improves focus and concentration
  • Stabilizes mood
  • Reduces physiological stress response
  • May enhance motivation
  • No addiction potential or withdrawal
  • Fast-acting — effects within 20–30 minutes
  • Approved clinically in Russia for anxiety disorders
Side Effects
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
  • Mild sedation at higher doses (paradoxical)
  • Fatigue (rare)
  • Irritability during discontinuation (uncommon)
Stacks With