Peptides for Skin

01GHK-Cusmall topical human trials only

the guide

the copper tripeptide and the only name here that sells in both worlds: a cosmetic ingredient under the name copper tripeptide-1 and a lyophilized research vial. in culture it raises fibroblast collagen synthesis, shifts decorin and glycosaminoglycans in rat wounds, and moves MMP-2 with its inhibitors.

evidence: the human trials are topical, small and split three ways. a multicenter randomized evaluator-blinded trial of a topical gel beat vehicle on diabetic neuropathic ulcers. a 0.4 percent cream did not beat placebo on venous stasis ulcers in 86 evaluable patients, where silver sulfadiazine did. after CO2 laser resurfacing, both arms of a 13-completer trial improved, the GHK-Cu products did not beat the regimen without them on wrinkles, skin quality or redness, and only patient-reported satisfaction differed. a 2026 review adds an 18-participant randomized, vehicle-controlled split-face study in which a 2 percent serum improved eyebrow hair count and diameter over 12 weeks; it measured hair, not skin, and is not separately indexed in PubMed. a phase 2 split-wound study of a topical gel in 60 healthy adults is recruiting, with primary completion listed for 14 February 2027 and no results.

watch for: no controlled human trial of injected or otherwise systemic GHK-Cu has been published; two 2026 sports medicine reviews say the same thing from the musculoskeletal side. the gene expression reset story traces to review articles by the ingredient's own developer, not to a clinical endpoint. copper crosses human skin ex vivo in quantity, roughly 136 mcg per square centimeter over 48 hours from a 0.68 percent solution, which cuts against the idea that a copper peptide stays on the surface. a 2026 chemistry review of the whole literature found that published studies rarely measure copper occupancy, labile copper or which species is actually present, and that the complex is redox active under some conditions. FDA lists injectable GHK-Cu among nominated-but-withdrawn bulk substances with an immunogenicity concern and limited human data.

02Palmitoyl Pentapeptide-4small human cosmetic trials

the guide

KTTKS with a palmitoyl tail. the five residues are a fragment of the type I procollagen propeptide, identified in 1993 as the shortest sequence that raised collagen and fibronectin output in cultured mesenchymal cells; the fatty tail was added because the bare fragment barely crosses skin.

evidence: the largest trial is Procter & Gamble's own: 93 women aged 35 to 55, 12 weeks, double-blind, split-face, a moisturizer with 3 ppm of the peptide against the same moisturizer, with significant improvement in fine lines and wrinkles by image analysis and expert grading. a 2023 double-blind randomized trial in 21 Indonesian women over 8 weeks compared it with acetyl hexapeptide-3 cream (another name for acetyl hexapeptide-8) and placebo for crow's feet and reported it as the better of the two. the laboratory work holds up: the palmitoylated peptide stimulates collagen production in human dermal and corneal fibroblasts in a concentration-dependent way near its aggregation threshold.

watch for: delivery is the weak point and it is measured. in hairless mouse skin both the plain and palmitoylated peptides degraded quickly in skin homogenate, neither crossed full-thickness skin into the receptor fluid, and only the palmitoylated form appeared in the skin layers, falling to a trace in the dermis. Procter & Gamble's two split-face studies of 42 and 35 women tested finished products holding niacinamide, carnosine and two peptides at once, so the peptide's own contribution cannot be read out of them. and the positive trial tested 3 ppm inside a formulated moisturizer, which is not the same object as a raw powder.

03Acetyl Hexapeptide-8small human cosmetic trials

the guide

six residues, Ac-EEMQRR-NH2, patterned on the N-terminal end of SNAP-25 and designed to compete for a place in the SNARE complex that lets nerve terminals release their contents. the SNARE-competition peptide with the most published trials of its own.

evidence: the 2002 design paper reported a 10 percent emulsion reducing wrinkle depth by up to 30 percent over 30 days, with inhibition of neurotransmitter release at a potency near botulinum toxin A and, as the authors state plainly, much lower efficacy than the toxin. a randomized placebo-controlled study in 60 Chinese subjects, treatment to placebo 3 to 1 for 4 weeks, found 48.9 percent subjective anti-wrinkle efficacy against 0 percent for placebo, with roughness parameters down on treatment and not on placebo. a 2023 double-blind split-face study in 19 women found no significant difference in wrinkle scores between a serum with the peptide and the same serum without it after 4 weeks. the 21-woman crow's feet trial above included it under its other name. one medical trial exists: 24 patients with blepharospasm on regular botulinum toxin injections, where the topical peptide produced a trend to longer symptom control, 3.7 months against 3.0, which did not reach significance.

watch for: an FDA laboratory applied a 10 percent emulsion to human cadaver and hairless guinea pig skin in diffusion cells and found almost all of it washed off, about 0.22 percent of the applied dose left in human stratum corneum, 0.01 percent in the epidermis, and none detected in the dermis or in the fluid beneath the skin. a peptide that does not reach a neuromuscular junction cannot act on one the way the toxin does. no head-to-head trial against botulinum toxin for wrinkles has been published, although the peptide is marketed as a cheaper alternative to it.

04Snap-8small human trials, mixtures only

the guide

acetyl octapeptide-3, two residues longer than acetyl hexapeptide-8 and built on the same idea of competing with SNAP-25 for the SNARE complex. a 2024 clinical paper gives its sequence as Ac-Glu-Glu-Met-Gln-Arg-Arg-Ala-Asp-NH2.

evidence: no randomized trial of Snap-8 on its own. the indexed human studies are multi-ingredient products. a 12-week monocentric study of hyaluronic acid microneedle patches holding acetyl octapeptide-3 plus four other actives reported periorbital fine lines down about 25.8 percent and hydration up about 15.4 percent. a 2024 split-face study of a dissolving microneedle patch containing 0.03 percent Snap-8, a vitamin C derivative and a lipid, 24 enrolled and 21 completed over 28 days, beat a plain hyaluronic acid placebo patch on roughness, water loss and eye lifting. in both cases the design cannot separate Snap-8 from what it was mixed with.

watch for: both indexed human studies were run with the companies that make the patches (Imperial Bioscience and Raphas), and no independent trial exists. it shares the class problem: large, water-loving, charged peptides cross the stratum corneum poorly, and a 2022 review of anti-wrinkle peptide delivery concludes that most of these peptides need an enhancement method to reach their targets in the skin at useful concentrations. two SNARE-competition peptides in one routine is doubling one lever with no study of the pair.

05GLOW Blendno data as a blend

the guide

a market name, not a molecule. in this site's own compound entry, GLOW is GHK-Cu with BPC-157 and TB-500, described as a blend for skin and recovery. BHG Labs does not list it.

evidence: nothing has been published on a GHK-Cu, BPC-157 and TB-500 preparation in any species. the component records do not match each other. GHK-Cu has the topical trials above. BPC-157's skin evidence is rodent work: burn, corticosteroid-impaired and CO2 laser wounds in mice from the Zagreb group behind most BPC-157 papers, and an alkali-burn model in rats from a group in Xi'an. TB-500 is a seven-residue acetylated fragment of thymosin beta-4, and a 2024 metabolite study states outright that the biological effects of TB-500 have not been documented, adding that the wound-healing activity reported in the literature may belong to a metabolite rather than the parent. the published human skin trials in this family used full-length thymosin beta-4, not the fragment: a phase 2 in venous stasis ulcers with about 70 patients across eight European sites, and a pressure ulcer phase 2 of the same size.

watch for: three names, three different evidence shapes, and a composition that comes from the market rather than from a label or a study. FDA's bulk substances page records no human exposure data for the thymosin beta-4 fragment, and no or only limited safety information for BPC-157. BPC-157 and thymosin beta-4 both promote new vessel growth in animal and cell work, which is the part of this that matters for anyone with a cancer history.

06KLOW Blendno data as a blend

the guide

the vial as sold: 80 mg total content, co-lyophilized, multi-component. the BHG Labs listing names no components and states only the total; the listing says composition and per-component quantitation are documented on the certificate for the lot. the four-name identity the market uses, GHK-Cu with BPC-157, TB-500 and KPV, comes from the name and not from the vendor.

evidence: no study of a four-component preparation of these peptides has been published in any species, which the site's own KLOW entry also says. the fourth name adds the thinnest record of the set: KPV, the C-terminal tripeptide of alpha-MSH, carries most of alpha-MSH's anti-inflammatory activity in review summaries, eased colitis in two mouse models, one chemical (DSS) and one T-cell transfer, sped corneal epithelial healing in rabbits, and protected cultured keratinocytes and a three-dimensional skin model against particulate matter. FDA states it has identified no human exposure data for KPV by any route of administration.

watch for: a certificate that gives one purity number and no per-component quantitation does not describe a blend. the questions to ask of the lot are whether it names each component, gives an amount for each, and reports a sequence or exact mass for each. copper is the chemistry risk in a shared vial: the 2026 review of GHK-Cu found labile copper and speciation rarely measured in published studies, and i could not locate any published compatibility or forced-degradation study of a copper peptide co-lyophilized with other peptides. the Tissue Repair Bench on this site takes the four names apart one at a time, including the FDA and anti-doping status of each, and that is the better page for that question.

palmitoyl pentapeptide-4, acetyl hexapeptide-8 and Snap-8 are cosmetic peptides whose human data are small trials of finished formulas, GHK-Cu sells both as a cosmetic ingredient and as a research vial, and GLOW and KLOW are multi-peptide blends named by the market. no study has tested GLOW or KLOW as sold. BodyHackGuide gives no amount, schedule or route for any compound on the skin bench. the Peptides for Skin bench covers 6 compounds: GHK-Cu, Palmitoyl Pentapeptide-4, Acetyl Hexapeptide-8, Snap-8, GLOW Blend, KLOW Blend, and BodyHackGuide publishes no protocol for any of them.