Skin & aging Brightening peptide
Nonapeptide-1
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- FDA approval
- Not FDA-approved for any use
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
If you think you are having a medical emergency, call 911.
Key takeaway
Nonapeptide-1 is a synthetic nine-amino acid peptide, sold as Melanostatine, used in skincare as a brightening ingredient. Laboratory work suggests it blocks a hormone signal that tells pigment cells to make melanin, which is the basis for its use in products aimed at the appearance of dark spots and uneven tone. As of 2026, the evidence is essentially laboratory data and manufacturer claims, with no published human trial of the ingredient.
At a glance
- What it is
- Cosmetic ingredient, a peptide used for skin brightening
- FDA status
- Does not require FDA approval, as a cosmetic ingredient rather than a drug
- Research
- Activity supported by laboratory data and manufacturer claims; human trials are lacking
- Used in
- Products targeting the look of dark spots, hyperpigmentation, and dullness
- Evidence strength
- Low research
Summary
Nonapeptide-1, sold as Melanostatine, is a skincare peptide used for dark spots. See how it works in the lab and what evidence exists for it.
What is nonapeptide-1?
Nonapeptide-1 is a synthetic peptide of nine amino acids, marketed in skincare under the name Melanostatine (for example, Melanostatine-5). It is used as a brightening ingredient, intended to help with the appearance of dark spots and uneven skin tone rather than to bleach the skin. It is a cosmetic ingredient, not a drug.
How does it work?
Laboratory studies describe nonapeptide-1 as a blocker of a specific pigment signal. Pigment-producing cells, called melanocytes, make more melanin when a hormone known as alpha-MSH binds to a receptor on their surface called MC1R. Nonapeptide-1 is designed to compete with alpha-MSH for that receptor, so the downstream signal to switch on melanin-making enzymes is dampened. In cell studies, it has been used as a reference antagonist that reduces melanin production.
The practical idea is prevention more than correction: By quieting the signal that drives new pigment, it is positioned to limit the appearance of future dark spots rather than to strip away existing ones. These are laboratory findings, and in finished products the benefit is described in appearance terms, such as a brighter, more even-looking complexion.
Is it FDA-approved?
Safety note
Status: Does not require FDA approval, as a cosmetic ingredient rather than a drug
Category: Cosmetic and topical · Primary body area: Skin & aging
No, and it does not need to be. The FDA does not pre-approve cosmetic ingredients. A cosmetic may describe effects on the look of skin tone, while a claim to treat a pigmentation disorder would make a product a drug. Nonapeptide-1 is used as a cosmetic ingredient, for the appearance of the skin.
What is it used for?
Nonapeptide-1 is used in brightening serums and creams aimed at the look of dark spots, hyperpigmentation, and overall radiance. It is commonly combined with other brightening ingredients such as niacinamide or vitamin C and, in practice, is used alongside daily sun protection, since UV exposure drives pigmentation.
What does the research show?
Editor’s note
Evidence strength: Low research
Its brightening activity is supported only by laboratory data and manufacturer claims, with no published human trial of the ingredient demonstrating an appearance benefit.
The evidence is thin and mostly laboratory-based. According to PubMed, nonapeptide-1 appears in a cell study where it served as a known alpha-MSH blocker used for comparison, confirming anti-pigment activity in the lab. The manufacturer reports brightening activity in skin, but no corresponding independent, peer-reviewed human trial of the ingredient was found. So the brightening rationale is supported in principle by laboratory work but not by published human appearance trials.
What are the side effects?
Nonapeptide-1 is generally reported as well tolerated and non-irritating at cosmetic use levels, and it is positioned as a gentler alternative to some older brightening agents. Independent human safety data are limited, so a patch test is reasonable for sensitive skin.
Sources: a cell study using nonapeptide-1 as an alpha-MSH antagonist reference (Chen et al., Advances in Dermatology and Allergology, 2022, DOI: 10.5114/ada.2022.115890), indexed on PubMed; and manufacturer and cosmetic ingredient reference data on Melanostatine. This document is educational and does not constitute medical advice.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
Compare every peptide’s status in the peptide regulatory status database
More for Skin & aging
View all skin & aging peptides →- Cosmetic & topical Skin & aging
Acetyl-Hexapeptide-8
Argireline
Acetyl hexapeptide-8, sold in skincare as Argireline, is a synthetic peptide modeled on the nerve protein SNAP-25 and marketed as a topical, "Botox-like" way to soften the appearance of expression lines. In lab and small clinical studies it interferes with the SNARE complex that nerves use to trigger muscle contraction, and a 2013 randomized study found it reduced the appearance of peri-orbital wrinkles over four weeks. It is a cosmetic ingredient rather than a drug, so it does not require FDA approval, and its evidence is rated Moderate.
- Cosmetic & topical Skin & aging
Acetyl-Octapeptide-3
SNAP-8
Acetyl octapeptide-3, sold in skincare as SNAP-8, is a synthetic eight-amino acid peptide modeled on the nerve protein SNAP-25 and marketed as a stronger successor to Argireline for softening the appearance of expression lines. Like Argireline, it is designed to interfere with the SNARE complex that nerves use to trigger muscle contraction, but its own published human evidence is thin and comes mostly from the manufacturer. It is a cosmetic ingredient rather than a drug, so it does not require FDA approval, and its evidence is rated Low.
- Cosmetic & topical Skin & aging
Acetyl-Tetrapeptide-5
Eyeseryl
Acetyl tetrapeptide-5, sold in skincare as Eyeseryl, is a synthetic four-amino acid peptide used in eye creams to soften the look of under-eye bags and puffiness. It is thought to work in two ways, by easing the fluid buildup that makes the under-eye area look swollen and by limiting the glycation that stiffens collagen, though its published evidence comes almost entirely from the manufacturer. It is a cosmetic ingredient rather than a drug, so it does not require FDA approval, and its evidence is rated Low.
- FDA-approved Skin & aging
Afamelanotide
Afamelanotide is a synthetic, longer-lasting analog of alpha-melanocyte-stimulating hormone (α-MSH) that activates the MC1R receptor on pigment cells to boost the skin's own protective eumelanin. The FDA approved it in 2019 as Scenesse, a subcutaneous implant for adults with erythropoietic protoporphyria (EPP), a rare light-sensitivity disorder. In the pivotal 2015 placebo-controlled trials, U.S. patients (94) logged a median 69.4 pain-free hours in direct sunlight versus 40.8 on placebo (P = 0.04). EU patients (74) logged 6.0 versus 0.8 hours (P = 0.005).
- FDA-approved Skin & aging
Bacitracin
Bacitracin is a cyclic polypeptide antibiotic produced by Bacillus bacteria that kills gram-positive bacteria by blocking the construction of their cell wall. It is best known as an over-the-counter topical ointment for preventing infection in minor cuts, scrapes, and burns, often combined with neomycin and polymyxin B in "triple antibiotic" products. It is widely available over the counter, but it is also a common cause of allergic skin reactions, and its injectable form was withdrawn over kidney-toxicity concerns.
- Cosmetic & topical Skin & aging
Carnosine
Carnosine is a naturally occurring dipeptide, made of the amino acids beta-alanine and histidine, used in skincare as an antioxidant ingredient. Laboratory and ex-vivo skin studies suggest it can neutralize reactive oxygen species and limit glycation, a process in which sugars stiffen skin proteins, which is the rationale for using it in products aimed at the appearance of aging skin. As of 2026, the evidence for topical carnosine is largely from lab and ex-vivo studies rather than large human appearance trials.