Evidence review: Open Peptide Project (verified against primary PubMed, ClinicalTrials.gov & FDA records) · Last checked 2026-10-27. ← Back to Evidence Library

Myristoyl pentapeptide-17: what the evidence says

Name: Myristoyl pentapeptide-17
Published: 2026-10-27

At a glance

What it is: a five-amino-acid peptide (lysine-leucine-alanine-lysine-lysine amide) with a fatty-acid (myristoyl) tail, used in eyelash and eyebrow serums. ^R1 It is listed as an ingredient of at least one lash serum studied for safety. ^R2 Trade names used by suppliers could not be confirmed. UNVERIFIED

What the evidence says: Unknown no published trial tested whether it grows lashes. Human A company-funded safety study of a lash and brow serum containing it (66 enrolled) found no safety signals. ^R2

Biggest risks: no safety signals in one multi-ingredient serum study. ^R2 A separate concern: some lash serums sold as peptide products have been found to contain undeclared prostaglandin-type drugs, which can darken the iris permanently. ^{R3, R4, R5}

Rating


Human Human evidence	Very limited: one safety study of a multi-ingredient serum, n = 66 ^R2
Animal Animal / lab evidence	Not reviewed
Regulatory	Cosmetic ingredient; not FDA-approved ^R6 · not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page ^{R7, R8, R9} · not named by WADA ^R10
Established human dose	No

Evidence verdict: Longer or fuller eyelashes: No human data for the peptide (no efficacy trial found) · Safety in a multi-ingredient lash serum: Very limited (one 66-person safety study)

This page reports what studies used. It is not dosing advice.

Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source

About the evidence: there is no efficacy evidence at all; the only human data are safety data for a multi-ingredient product, from a study funded by the product's maker.

What is it?

Does it work?

Unknown Lash growth: no published trial of this peptide found (PubMed searched Oct 27, 2026).
Human Safety: in a company-funded study of a lash and brow serum listing it as an ingredient, 66 people enrolled and 55 finished; no safety signals and no changes in eye exams. ^R2

How it compares with the prescription option

Human Bimatoprost (Latisse) is FDA-approved for thin eyelashes, with trial data behind it; its label warns of eyelid darkening and iris darkening that is likely permanent. ^{R11, R5}
Human Testing has found prostaglandin-type drugs, not always declared, in many lash serums: 12 of 64 in one study and about 30% of 79 in another. ^{R3, R4} Bimatoprost-type drugs have also been linked to loss of fat around the eye. ^R12

Is it safe?

Human No safety signals in the one serum study. ^R2
Human Undeclared prostaglandin-type drugs in some lash serums are the main hidden risk. ^{R3, R4}
Stop using any lash product that causes eye redness or irritation.

Gray-market vials: extra risks

A gray-market vial has no quality control and no guarantee of identity, strength or sterility. We test retail vials blind under the Open Peptide Standard; see /tests/. A passing test covers one batch on one date and does not mean the compound is safe.

Is it legal?

US: sold as a cosmetic ingredient. Cosmetics do not need FDA approval before sale; products making drug-type claims can be regulated as drugs. ^R6 No Drugs@FDA application found (openFDA searched Oct 27, 2026).
Compounding: not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page. ^{R7, R8, R9}
Sport: not named on WADA's 2026 Prohibited List. ^R10

Study details

These are amounts researchers used, not recommendations.

Study	People / model	Route	Amount used	Follow-up	Reported	Citation
Wesley 2024 (safety study)	66 adults (55 completed)	Topical lash and brow serum (multi-ingredient)	Per product	Per study	No safety signals	PMID 39479552

Full reference list (PubMed, CT.gov, FDA and WADA checked Oct 27, 2026)

^R1 PubChem CID 127264611, Myristoyl Pentapeptide-17 (N2-(1-oxotetradecyl)-L-lysyl-L-leucyl-L-alanyl-L-lysyl-L-lysinamide), checked Oct 27, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/127264611
^R2 Wesley G, et al. Clin Ophthalmol. 2024. PMID 39479552
^R3 Rahman MS, et al. J Pharm Biomed Anal. 2022. PMID 35882176
^R4 Couteau C, et al. Ann Pharm Fr. 2026. PMID 42269767
^R5 Latisse prescribing information, label published Jul 1, 2024 (DailyMed, checked Oct 27, 2026). https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=34f83d9d-2c64-463e-8a90-9a460fedfead
^R6 FDA. Is It a Cosmetic, a Drug, or Both? (Or Is It Soap?) Content current as of Sep 11, 2024. https://www.fda.gov/cosmetics/cosmetics-laws-regulations/it-cosmetic-drug-or-both-or-it-soap
^R7 FDA, 503A bulk drug substances categories list (updated May 14, 2026). https://www.fda.gov/media/94155/download
^R8 FDA, 503B bulk drug substances categories list (updated Mar 21, 2025). https://www.fda.gov/media/94164/download
^R9 FDA, Certain bulk drug substances for use in compounding that may present significant safety risks (content current Apr 22, 2026). https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
^R10 WADA. The 2026 Prohibited List, full list checked; compound not named. https://www.wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf
^R11 Drugs@FDA, Latisse (bimatoprost ophthalmic solution), application NDA022369 (openFDA drugsfda record checked Oct 27, 2026). https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=NDA022369
^R12 Sira M, et al. Aesthet Surg J. 2012. PMID 22942109

Disclaimer

This page is for education and harm reduction, not medical advice or a recommendation to use Myristoyl pentapeptide-17. This is a cosmetic ingredient, not an FDA-approved drug. Cosmetic products are not reviewed by FDA for effectiveness before sale. Report problems to FDA MedWatch (https://www.fda.gov/safety/medwatch).