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ToolsCompareSemax vs Pentapeptide-18

Semax vs Pentapeptide-18

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

Cognitive Enhancement
Semax
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
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.
Half-Life
Minutes (but effects persist for hours via BDNF induction)
Not applicable (topical)
Admin Route
Intranasal, SubQ
Topical
Research
Typical Dose
0.25–1 mg (250–1000 mcg)
0.005–0.05% in formulation
Frequency
1–2 times daily
Twice daily
Key Benefits
  • Enhances memory and learning
  • Improves focus and concentration
  • Increases mental energy and motivation
  • Provides neuroprotection via BDNF and NGF upregulation
  • Reduces cognitive decline
  • May alleviate ADHD symptoms
  • Supports recovery from brain injury and stroke
  • Fast-acting — effects within 30–60 minutes
  • Approved in Russia for cognitive disorders and stroke recovery
  • 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
Side Effects
  • Headache (rare, often from higher doses)
  • Anxiety or overstimulation at high doses
  • Sleep disruption if dosed too late
  • Irritability (uncommon)
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
Stacks With