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Leuphasyl

low risk

Also: Pentapeptide-18 · Lipopeptide-18

Preliminary Research Only

Leuphasyl is a pentapeptide analog of enkephalin that modulates facial neuromuscular function through a mechanism distinct from argireline. It targets delta-opioid receptors on neurons rather than SNARE complex components.

Molecular Weight
596.7 g/mol
Formula
C29H48N6O7
Common Dosing
Topical: 2-5% in formulation
Category
cosmetic
Last Reviewed
2025-01-15

Reported Benefits

Expression Line Reduction

Preliminary 6 studies

Manufacturer-sponsored studies show wrinkle depth reduction.

Synergy with Argireline

Preliminary 4 studies

Combination with argireline shows additive wrinkle reduction.

Mechanism of Action

Leuphasyl mimics the endogenous opioid enkephalin, binding to delta-opioid receptors on peripheral neurons. This reduces cAMP levels and calcium-dependent neurotransmitter release — a different mechanistic approach to reducing neuromuscular transmission than SNAP-complex inhibitors like argireline.

Key Clinical Studies

Lipotec study (2009)

manufacturer · Clinical evaluation

Leuphasyl reduces crow's feet wrinkle depth in combination protocols

Overview

Leuphasyl represents a different mechanistic approach to cosmetic peptide-based wrinkle reduction — using opioid receptor modulation rather than SNARE complex inhibition. The enkephalin-based mechanism is pharmacologically distinct from argireline/SNAP-8, providing rationale for combination use.

Enkephalin Mechanism

Enkephalins are endogenous opioid pentapeptides (Met-enkephalin and Leu-enkephalin) that modulate pain and neural signaling. Leuphasyl’s structural similarity to enkephalin allows it to activate peripheral delta-opioid receptors, reducing neurotransmitter release through a cAMP-dependent mechanism.

Evidence Quality

Like most cosmetic peptides beyond argireline and matrixyl, leuphasyl’s evidence base is largely manufacturer-sponsored with limited independent validation. The combination studies with argireline are mechanistically compelling but lack independent replication.

Market Position

Leuphasyl is primarily positioned as a complementary ingredient to argireline in anti-aging formulations rather than as a standalone active. The dual-mechanism rationale makes it appealing for formulators seeking comprehensive expression line reduction.

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Nava Health

Regulatory Status

Research Only

Cosmetic ingredient; INCI name Pentapeptide-18; no FDA drug approval

Safety Profile

Side Effects

  • Skin irritation (rare)

Contraindications

  • None established

Drug Interactions

  • None established

Primary Uses

Expression line reductionEnkephalin-based wrinkle treatmentAnti-aging

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.