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ToolsComparePentapeptide-18 vs Nonapeptide-1

Pentapeptide-18 vs Nonapeptide-1

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & Cosmetic
Nonapeptide-1
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.
Nonapeptide-1 is a synthetic 9-amino acid peptide that inhibits melanin production by blocking α-MSH (alpha-melanocyte stimulating hormone) receptor binding. Used in cosmetic formulations for skin lightening and evening skin tone, it is particularly effective for UV-induced and hormonal hyperpigmentation.
Half-Life
Not applicable (topical)
Not applicable (topical)
Admin Route
Topical
Topical
Research
Typical Dose
0.005–0.05% in formulation
0.05–0.5% concentration in formulation
Frequency
Twice daily
Twice 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
  • Inhibits UV-induced tanning and hyperpigmentation
  • Reduces hormonal melasma
  • Evens skin tone at receptor level
  • Well-tolerated with minimal irritation
  • Complementary to tyrosinase inhibitors for enhanced brightening
  • Reduces post-inflammatory hyperpigmentation
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)
  • Generally very well-tolerated
  • Rare contact sensitivity in susceptible individuals
  • Theoretical risk of excessive depigmentation with prolonged high-concentration use
Stacks With