Palmitoyl pentapeptide-4
Palmitoyl pentapeptide-4 is a lipid-linked cosmetic peptide, often described as pal-KTTKS, studied in moisturizers for visible facial aging.
At a glance
- Regulatory status
- Cosmetic ingredient; cosmetic marketing or an ingredient listing is not FDA drug approval. Claims and intended use determine regulatory treatment.
- Research context
- Palmitoyl pentapeptide-4 is a lipid-linked cosmetic peptide, often described as pal-KTTKS, studied in moisturizers for visible facial aging.
What this is
- Palmitoyl pentapeptide-4 is a lipid-linked cosmetic peptide, often described as pal-KTTKS, studied in moisturizers for visible facial aging.
What this isn't
- A recommendation to use, prepare, combine, or administer a product
- Evidence that a related molecule or a differently formulated product has the same effects
Palmitoyl pentapeptide-4 is a lipid-linked cosmetic peptide, often described as pal-KTTKS, studied in moisturizers for visible facial aging.
Its KTTKS sequence was developed around an extracellular-matrix signaling hypothesis. Attaching a fatty-acid group changes the molecule and its formulation properties. The clinical question is whether a product improves visible outcomes beyond its moisturizer base, not simply whether a related fragment affects cells. Study rationale.
Evidence limits
How to read the evidence
Palmitoyl pentapeptide-4 is distinct from the two-peptide Matrixyl 3000 blend and from palmitoyl tripeptide-38. A shared commercial family name cannot transfer one formulation's results to another. The short trial does not establish lasting tissue rejuvenation, benefit across all skin types, or superiority to every established skincare option.
Sources appraised 2026-10-28. Educational information; not medical advice. Study findings apply to the populations, preparations and outcomes described.
External sources and citations
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