Acetyl Tetrapeptide-3_Dosage, benefits & legal status
Also known as Capixyl, tetrapeptide-3, acetyl tetrapeptide 3
A hair peptide sold for thinning, with evidence that mostly belongs to a combination product.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Acetyl Tetrapeptide-3?
Plain language first. The technical label stays, but it never stands alone.Overview
A hair peptide. It is meant to help hair stay put rather than to grow new hair, and most of the impressive numbers come from a blended product it was one ingredient in.
A synthetic tetrapeptide marketed for androgenetic alopecia and telogen shedding. Manufacturer in vitro data reports increased type III collagen and laminin expression in dermal papilla and scalp tissue. Human data derives from studies of a proprietary blend combining the peptide with Trifolium pratense extract, so the isolated contribution of the peptide is unquantified.
What it's used for
A scalp peptide used for thinning hair and weak anchoring, usually as part of a branded blend rather than on its own.
How does Acetyl Tetrapeptide-3 work?
What it does in the body, and where.This peptide is sold to strengthen how firmly a hair sits in the scalp, rather than to grow new hair directly.
- 01It signals for more anchoring proteinsManufacturer laboratory work reports increased production of type III collagen and laminin, which are part of the matrix holding a follicle in place.
- 02A better-anchored follicle sheds laterThe claim is not that new follicles appear. It is that existing ones stay put longer, which shows up as less shedding rather than more hair.
- 03Almost every number you will see is for a blendThe widely quoted 46% improvement in the growth-to-shedding ratio comes from a manufacturer study of a combination product containing red clover extract, not of this peptide alone.
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.
- Reducing hair shedding and supporting follicle anchoring, applied to the scalpSupplement or cosmetic
- Improving eyelash length and thicknessEarly research
- Reducing inflammation around hair folliclesEarly research
The published record
Papers and trials about Acetyl Tetrapeptide-3
Furthest stage reached: No clinical trial on record
Counted from Europe PMC indexing, not read by a person; a human tag can land on reviews, commentary or lab papers; clinical trial publications is the narrower count.
At a glance
Four things to know about Acetyl Tetrapeptide-3
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 or scalp treatment, 0.1 to 5%, daily. Not cycled Community practice
Used daily as part of a routine. The effect depends on continued use and fades 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 is how much crosses the skin and how long it stays in the tissue, which is a different measurement and 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.Acetyl Tetrapeptide-3 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.
Acetyl Tetrapeptide-3 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.Who should avoid it
- Broken or actively inflamed scalp skin
- A known allergy to any component of the finished product
Stop and get help
- A spreading rash or significant swelling where applied
Common effects
- Very well tolerated in cosmetic use.
- Occasional scalp irritation, usually from other ingredients in the formula.
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Acetyl Tetrapeptide-3 approved?
And where the numbers on this page come from.Not as a medicine. Acetyl Tetrapeptide-3 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
We have not yet written a full regulatory note for this compound. The status above is current as of the date shown.
You can compare this against the whole library, or read how to check a seller.
What else is like Acetyl Tetrapeptide-3?
Others in Skin and cosmetic, side by side.If you're weighing Acetyl Tetrapeptide-3, it's worth reading Acetyl Tetrapeptide-5 (Eyeseryl), Biotinoyl Tripeptide-1, and Hexapeptide-11 in the same class.
A hair peptide sold for thinning, with evidence that mostly belongs to a combination product.
- Dose
- Serum or scalp treatment, 0.1 to 5%
- How often
- Daily
A topical peptide aimed at under-eye puffiness rather than lines.
- Dose
- Serum, per product
- How often
- Daily
GHK with a biotin tail, sold for hair and lashes rather than skin.
- Dose
- Serum, 2 to 6 ppm typical in a finished product
- How often
- Daily
A yeast-derived cosmetic peptide for elasticity, with a thin evidence trail.
- Dose
- Serum, 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
Beyond these, 2 records are indexed. Browse the records