Myristoyl Pentapeptide-17_Dosage, benefits & legal status
Also known as SymPeptide 226EL, myristoyl pentapeptide 17, lash peptide
The lash-serum peptide, used where people want to avoid prostaglandins.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Myristoyl Pentapeptide-17?
Plain language first. The technical label stays, but it never stands alone.Overview
The peptide in most lash serums that avoid prostaglandins. Slower and safer than the prescription drops, and nobody selling it can agree on what it is actually made of.
Myristoyl pentapeptide-17, a topical lipopeptide marketed as SymPeptide 226EL, COSING reference 85279, used at roughly 0.001 to 0.1 percent in periocular leave-on products. Claimed activity is upregulation of keratin gene expression in the follicle. Published sequences are inconsistent and no independent single-ingredient trial has been published.
What it's used for
A topical peptide used in lash and brow serums for longer, thicker-looking hair.
How does Myristoyl Pentapeptide-17 work?
What it does in the body, and where.This peptide is the reason many lash serums can advertise results without using a prostaglandin.
- 01The fatty acid is there to get it through skinMyristic acid is a fourteen-carbon fatty acid attached to the front of the peptide. The oily tail helps it cross the outer layer of skin, which a bare peptide struggles to do.
- 02The claimed action is on keratinKeratin is the structural protein a hair is made of. More of it is proposed to mean a thicker, stronger shaft rather than more hairs.
- 03The real comparison is prostaglandin analogsBimatoprost and its relatives work, and they carry documented risks including permanent iris darkening and orbital fat loss. Peptide serums are slower and much gentler, and the honest trade is a smaller result for a smaller risk.
Where this compound is thought to act.
What else is it used for?
Each use below carries its own evidence level. Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
- Longer and thicker-looking lashes and brows, applied to the lash lineSupplement or cosmetic
- Supporting keratin production in the hair shaftEarly research
- Scalp hair productsnone
- Paired with myristoyl hexapeptide-16 or biotinoyl tripeptide-1 in multi-peptide serumsnone
The published record
0
Papers and trials about Myristoyl Pentapeptide-17
Europe PMC was searched on 12 October 2026 and returned nothing.
Counted from Europe PMC indexing, not read by a person.
At a glance
Four things to know about Myristoyl Pentapeptide-17
Evidence
Cosmetic
Category
Skin and cosmetic
Common vial
Varies
Half-life
Not measured, and not the right question
How much, and do you cycle it?
The range, and whether you take breaks.Serum, per product, daily. Not cycled Community practice
Used daily as part of a routine. The effect depends on continued use and returns to baseline when you stop, so there is nothing to cycle off.
Not measured, and not the right questionNo figure
This is a topical cosmetic ingredient. A blood half-life measures how fast something leaves the bloodstream, and these are not intended to reach it in meaningful amounts. What matters for a topical is how much penetrates the skin and how long it stays in the tissue, which is a different measurement and one that is rarely published.
You can compare this against the whole library to see where it sits.
What does it cost?
Typical dose and cost, in plain numbers.Myristoyl Pentapeptide-17 is not injected
It is taken on the skin (topical). Applied as a topical product at the concentration the manufacturer sets. There is no injected dose.
How do you store it?
Before mixing, and after.Room temperature, out of light. Cap it tight after each use.
Myristoyl Pentapeptide-17 ships as a cream, gel, or serum. Keep it at room temperature away from sun and heat unless the label says otherwise. Refrigerating an emulsion can split the texture. Watch for color, smell, or separation changes and stop using it if any appear.
What are the side effects and cautions?
Known cautions and warnings for this compound.Solubility, computed: 100% charged residues, 40% hydrophobic. Water usually sufficient.
A first-pass rule from peptide manufacturers' guidance. It does not account for disulfide bridges, salt form or how the powder was dried, and it predicts what should be easy rather than what will happen in your vial.
Who should avoid it
- A known allergy to this ingredient or to others in the same product
- Broken, cracked, or actively irritated skin
- Use inside the eye or on the waterline, since lash products are meant for the skin above the lash line only
- Anyone who wants established safety data, because none exists for this compound in humans
Stop and get help
- A rash that spreads beyond where you applied it
- Swelling of the face, lips, or eyelids, or any trouble breathing
- Burning that does not settle after rinsing it off
- Redness, itching or swelling of the eyelid
- Any change in vision
- Anything unusual, since there is no known safety profile to compare it against
Common effects
- Reactions are not commonly reported, though no published testing has looked for them. Irritation from a product containing it may come from anything else in the formula.
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Myristoyl Pentapeptide-17 approved?
And where the numbers on this page come from.Not as a medicine. Myristoyl Pentapeptide-17 is sold without a prescription as a cosmetic ingredient, which is a different thing from being approved as a drug.
- Approval statusCosmeticSold without a prescription as an ingredient in cosmetics, such as skincare and hair products. The FDA does not approve cosmetics before they are sold, and being easy to buy says nothing about whether it works.
- RouteOn the skin (topical)
- Checked24 August 2026
- DoseFrom the concentration range manufacturers formulate at. This is a product strength, not a dose set by a regulator or a trial.
- Vial sizeFrom what vendors typically list; not a recommendation.
- SourcesNone traced yet.
What has happened recently
Regulated as a cosmetic ingredient, not a drug. Cosmetic ingredients are not reviewed for effectiveness before sale in the US, so a product may legally claim an appearance benefit without a trial behind it.
You can compare this against the whole library, or read how to check a seller.
What else is like Myristoyl Pentapeptide-17?
Others in Skin and cosmetic, side by side.If you're weighing Myristoyl Pentapeptide-17, it's worth reading Oligopeptide-1 (EGF), Palmitoyl Tripeptide-38, and Palmitoyl Tripeptide-8 in the same class.
The lash-serum peptide, used where people want to avoid prostaglandins.
- Dose
- Serum, per product
- How often
- Daily
Epidermal growth factor under a cosmetic name, and the only real protein on this shelf.
- Dose
- Serum, per product
- How often
- Daily
The peptide behind Matrixyl synthe'6, a topical anti-wrinkle ingredient from Sederma.
- Dose
- Serum or cream, per product
- How often
- Twice daily (supplier study)
A skin-calming ingredient built from three residues of a natural anti-inflammatory hormone, backed mainly by supplier tests.
- Dose
- Serum or cream, per product
- How often
- Daily
Guides for this compound
- mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
- How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.
- How to Vet a Peptide Vendor
Independent COAs, HPLC purity, and the red flags that mean walk away.
Sources
No primary source has been traced for this compound yet. Treat everything on this page as unverified until one is. How we grade evidence