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ToolsComparePentapeptide-18 vs DSIP

Pentapeptide-18 vs DSIP

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Sleep OptimizationCognitive Enhancement
DSIP
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.
DSIP is an endogenous neuropeptide originally isolated from rabbit cerebrospinal fluid that induces delta-wave (deep) sleep. It also modulates stress response, cortisol regulation, and LH secretion, making it valuable for sleep optimization and stress management.
Half-Life
Not applicable (topical)
~30–60 minutes; however downstream sleep effects last 4–6 hours
Admin Route
Topical
SubQ, IV, Intranasal
Research
Typical Dose
0.005–0.05% in formulation
100–400 mcg
Frequency
Twice daily
Once nightly
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
  • Induces and deepens delta-wave (slow-wave) sleep
  • Reduces cortisol and normalizes HPA axis
  • Improves sleep quality in insomnia patients
  • Anti-stress and anxiolytic effects
  • May improve opiate/alcohol withdrawal symptoms
  • Analgesic properties through opioid modulation
  • Antioxidant and neuroprotective effects
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 well tolerated
  • Mild grogginess next morning at higher doses
  • Rare: hypotension
  • Potential for altered dream patterns
Stacks With