Polyepsilon-Lysine
INCI: POLYEPSILON-LYSINE
Reviewed by Rosie · Last updated 14 Aug 2026
A conditioning polymer that supports skin and hair structure
Best For Skin Types
All
Addresses
Usage Frequency
Daily
What Is Polyepsilon-Lysine?
Polyepsilon-lysine is a synthetic polypeptide—a chain of amino acids—derived from lysine, one of the building blocks of proteins. It functions as a conditioning agent in skincare and haircare formulations.
In skincare products, polyepsilon-lysine works primarily as a skin conditioning agent, helping to improve the texture and feel of formulations whilst supporting the skin's surface.
How It Works
Polyepsilon-lysine conditions skin by forming a light film on the surface, which can help reduce water loss and improve how the skin feels to the touch. Its polymer structure allows it to coat and smooth the outer layers of skin.
Clinical Evidence & References
Evidence specifically evaluating polyepsilon-lysine in skincare is limited in published literature. The ingredient is primarily included in formulations for its conditioning properties based on its chemical structure as a polypeptide.
Whilst amino acid-derived ingredients and polypeptides are widely used in cosmetics, further research would strengthen our understanding of polyepsilon-lysine's specific efficacy in addressing skin concerns.
How to Use
Polyepsilon-lysine is typically used as a supporting ingredient within a broader skincare formula rather than as a standalone treatment. It is generally well-tolerated and can be used daily as part of your regular skincare routine.
Safety & Precautions
Frequently Asked Questions
From the Clinic
Not sure what your skin actually needs?
Two minutes, a few questions, and we’ll point you at what matters — no guesswork.
Take the skin quizRelated Ingredients
Pollen
A botanical conditioning agent derived from plant pollen with skin-soothing properties
Polyamide-5
A synthetic polymer that conditions and smooths the skin surface
Polydecene
A synthetic oil that conditions skin and improves product texture
Polygala Tenuifolia Root Extract
A plant-derived conditioning agent with traditional use in herbal medicine
Polyglyceryl-10 Eicosanedioate/Tetradecanedioate
A conditioning agent that helps support skin and hair moisture retention
Polyglyceryl-10 Isostearate
A synthetic emollient that conditions and softens the skin barrier
Learn More About Skincare Ingredients
Explore our comprehensive ingredient glossary to understand what's in your products.
Browse All IngredientsShop Our Products
Find professional skincare solutions at Skintique.