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Leuphasyl
Also known as Pentapeptide-18, enkephalin analogue.
Best known for The peptide formulated alongside Argireline
Evidence★★☆☆☆
Safety dataWell characterised
Route Topical
United StatesCosmetic ingredient: lawfully sold
AustraliaCosmetic ingredient: lawfully sold
as at 16 September 2026
What it is and what it does
Leuphasyl is Pentapeptide-18, a cosmetic peptide modelled on enkephalin and a lawful cosmetic ingredient. It is studied for reducing expression lines, with limited human topical data, and is very commonly combined with Argireline.
What the full entry covers
The book carries the rest of this entry:
- Where the research stands, with every claim cited
- What people commonly ask, and what the research shows so far
- Dosing in four labelled bands, described and not recommended
- Side effects, serious risks, cautions and interactions
- Questions to discuss with your doctor
- How it compares with Argireline, SNAP-8, Syn-Ake, Matrixyl
Related entries
A certificate of analysis tells you what is in a vial. The evidence rating above tells you whether the compound has been shown to work in humans. Neither answers the other's question. How to read a certificate of analysis.
This page describes what is known and not known about Leuphasyl. It is not medical advice and not a recommendation to use it.