Pentapeptide-18 vs Oxytocin
Side-by-side comparison of key properties, dosing, and research.
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18Cognitive EnhancementSexual Health & Libido
Oxytocin- 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.
- Oxytocin is a 9-amino acid neuropeptide produced in the hypothalamus with diverse roles in social bonding, trust, stress reduction, and sexual function. Exogenous administration is used therapeutically to improve social cognition, reduce anxiety, and enhance intimacy.
- Half-Life
- Not applicable (topical)
- ~3–5 minutes (IV); ~30–60 minutes (intranasal, CNS effects persist longer)
- Admin Route
- Topical
- Intranasal, SubQ, IV
- Research
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- Typical Dose
- 0.005–0.05% in formulation
- 20–40 IU
- Frequency
- Twice daily
- As needed (not daily long-term)
- 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
- Enhances social bonding and trust
- Reduces social anxiety and fear of rejection
- Improves autism spectrum symptoms (social cognition)
- Reduces cortisol and stress reactivity
- Enhances sexual arousal and intimacy
- Promotes maternal behavior and bonding
- May improve depressive symptoms
- Appetite suppression and metabolic 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)
- Mild uterine cramping (avoid in pregnancy)
- Nasal irritation (intranasal)
- Headache
- Potential emotional over-attachment or jealousy amplification
- +2 more
- Stacks With
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