Skin & Hair Peptides

Also: Copper Peptide, Glycyl-L-histidyl-L-lysine copper

GHK-Cu is the copper(II) complex of GHK, a naturally occurring human tripeptide (glycyl-L-histidyl-L-lysine) found in blood plasma, saliva and urine, whose levels decline with age. It is researched and widely used in cosmetic skincare for skin regeneration, wound healing, collagen support and anti-aging. It is not an FDA-approved drug; it appears in over-the-counter cosmetics and as a research or compounded peptide, with most human evidence coming from small topical-skincare studies.

Also: Acetyl Octapeptide-3, SNAP-8

SNAP-8 (Acetyl Octapeptide-3) is a synthetic eight-amino-acid topical cosmetic peptide, an extended cousin of Argireline that adds two residues to the same SNAP-25 mimic sequence. It is marketed as a needle-free way to soften expression lines, especially on the forehead and around the eyes. It is a cosmetic ingredient, not an approved drug, and the human evidence behind it is thin and mostly comes from the manufacturer.

Also: Acetyl Hexapeptide-3, Acetyl Hexapeptide-8

Argireline is the trade name for acetyl hexapeptide-8 (sequence Ac-Glu-Glu-Met-Gln-Arg-Arg-NH2, also called acetyl hexapeptide-3), a synthetic peptide sold in anti-aging creams as a topical, needle-free alternative to Botox. It is designed to relax the muscle contractions behind expression lines. It is a cosmetic ingredient, not an FDA-approved drug, and the human efficacy data are genuinely mixed rather than settled.

Also: Palmitoyl Pentapeptide-4, Pal-KTTKS

Matrixyl is the trade name (Sederma) for palmitoyl pentapeptide-4, also written Pal-KTTKS, a collagen-fragment peptide attached to a fatty acid so it can cross skin. Unlike Botox-mimic peptides, it does not touch muscle: it signals skin cells to rebuild collagen, so it is aimed at fine lines, firmness and skin texture rather than expression wrinkles. It is a cosmetic ingredient with one of the better-documented topical studies in the peptide space, though far short of drug-grade proof.

Also: Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7

Matrixyl 3000 is Sederma's follow-up to the original Matrixyl, a fixed pair of two fatty-acid-tagged peptides: palmitoyl tripeptide-1 (Pal-GHK) and palmitoyl tetrapeptide-7 (Pal-GQPR). The idea is a one-two punch: one peptide tells skin to rebuild collagen, the other calms the low-grade inflammation that wears collagen down. It is a cosmetic ingredient aimed at firmness, fine lines and aging skin, with supportive but mostly company-generated evidence.

Also: Tripeptide-3, Ala-His-Lys Copper

AHK-Cu is a synthetic copper-bound tripeptide, alanine-histidine-lysine complexed with a copper ion, engineered mainly for hair and scalp products. It is the lesser-known sibling of the naturally occurring GHK-Cu copper peptide, designed in the lab specifically to push hair follicles to keep growing. It is a cosmetic and research ingredient, not an approved hair-loss drug, and its evidence is essentially limited to one notable lab study.

Also: Afamelanotide, Scenesse

Melanotan I is the research name for afamelanotide (code CUV1647), a 13-amino-acid synthetic analog of alpha-melanocyte-stimulating hormone (alpha-MSH), also written as [Nle4, D-Phe7]-alpha-MSH or NDP-MSH. Sold as Scenesse, it was approved by the EMA in 2014 and the FDA in 2019 to increase pain-free light exposure in adults with erythropoietic protoporphyria (EPP), one of a few approved melanocortin drugs alongside bremelanotide (Vyleesi) and setmelanotide (Imcivree). The approval covers only the 16 mg bioresorbable implant placed under the skin by a clinician. The injectable 'Melanotan I' sold online is not approved for anything.

Also: CXXC5-Dishevelled disrupting peptide, Protein Transduction Domain-Dishevelled Binding Motif

PTD-DBM is a synthetic peptide studied for hair regrowth. It pairs a cell-penetrating protein transduction domain with a Dishevelled-binding motif, letting it slip into cells and block CXXC5, a natural brake on the Wnt/beta-catenin pathway that hair follicles use to enter their growth phase. In mouse studies, releasing that brake (usually alongside topical valproic acid) restarted hair growth and even formed new follicles in wounded skin. The honest catch: the entire efficacy record is preclinical and comes mostly from one lab. There are no completed human trials, no regulatory approval, and no proof it works on people. For research use only.

Also: Matrixyl synthe'6, Matrixyl Synthe 6

Palmitoyl tripeptide-38 is the active in Sederma's Matrixyl synthe'6, a newer member of the Matrixyl family launched around 2011. It is a three-amino-acid fragment with a fatty acid tail, sold as a wrinkle 'filler from the inside' for forehead lines and crow's feet. It is a cosmetic ingredient, not a drug, and the honest picture is simple: the efficacy claims come almost entirely from the company that makes it.

Also: Eyeseryl, Ac-beta-Ala-His-Ser-His

Acetyl tetrapeptide-5 is a short synthetic peptide sold by Lipotec (now Lubrizol) as Eyeseryl, made for eye creams that target under-eye puffiness. The pitch is that it reduces fluid leaking into the tissue under the eyes. It is a cosmetic ingredient, and nearly all of the human data comes from the company that sells it.

Also: Collaxyl, Collaxyl IS

Hexapeptide-9 is a collagen-inspired signaling peptide sold as Collaxyl (originally from Vincience, now Ashland) for anti-wrinkle and firming skincare. The idea is that a small repeat of a collagen sequence nudges skin cells to rebuild the junction between the outer and inner skin. It is a cosmetic ingredient, and the evidence for the original peptide is mostly old, small and company-run, although a 2025 trial on a modified cyclic version is more interesting.

Also: Leuphasyl, Tyr-Ala-Gly-Phe-Leu

Pentapeptide-18 is Lipotec's Leuphasyl, a 'Botox-like' cosmetic peptide modeled on enkephalins, the body's own calming neuropeptides. It is mostly sold alongside Argireline, with the claim that the two relax expression lines better together. It is a cosmetic ingredient, and the evidence is small and mostly manufacturer-run.

Also: Dipeptide diaminobutyroyl benzylamide diacetate, SYN-AKE

SYN-AKE is DSM's trade name for dipeptide diaminobutyroyl benzylamide diacetate, the 'snake venom' peptide in a lot of anti-wrinkle creams. The marketing says it mimics Waglerin-1, a toxin from the temple viper. To be clear: there is no venom in it. It is a tiny synthetic molecule, and the evidence that it relaxes wrinkles comes almost entirely from the manufacturer.

Also: Biopeptide EL, Pal-VGVAPG

Palmitoyl hexapeptide-12 is the six-amino-acid sequence VGVAPG, a repeating piece of elastin, with a fatty acid tail attached so it can get into skin. It is sold under the trade name Biopeptide EL and pitched for firmness and elasticity, the bounce-back that fades with age. It is a cosmetic ingredient, not an FDA-approved drug, and nobody has published an independent clinical trial showing it visibly changes skin.

Also: Decorinyl, Decorin-like tetrapeptide

Tripeptide-10 citrulline, sold as Decorinyl, is a small synthetic peptide (four residues, despite the name) designed by the Spanish ingredient maker Lipotec to mimic decorin, a protein that keeps collagen fibers neat and evenly sized. The pitch is better collagen, not more collagen. It is a cosmetic ingredient, not an FDA-approved drug, and almost all of the evidence comes from the company that makes it.

Also: sh-Oligopeptide-1, rh-Oligopeptide-1

sh-Oligopeptide-1 is the cosmetic ingredient name for recombinant human epidermal growth factor (EGF), a 53-amino-acid protein your skin uses to tell cells to divide and repair. It shows up in 'EGF serums' aimed at wrinkles, texture and post-procedure recovery. It is a cosmetic ingredient in skincare, not an FDA-approved drug for skin aging, and while there are a fair number of small human studies, very few are properly controlled.

Also: Melanostatine 5, Melanostatine-5

Nonapeptide-1, sold as Melanostatine 5, is a nine-amino-acid synthetic peptide built to block alpha-MSH, the hormone that tells pigment cells to make melanin. It goes into brightening and dark-spot products as a gentler alternative to harsh lighteners. It is a cosmetic ingredient, not an FDA-approved drug, and there is no independent peer-reviewed clinical trial of it on its own.