Tripeptide-29_Dosage, benefits & legal status
Also known as Gly-Pro-Hyp, GPH tripeptide, collagen tripeptide
A three-amino-acid collagen fragment sold as a signal for firmer skin.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Tripeptide-29?
Plain language first. The technical label stays, but it never stands alone.Overview
Skin cells may read small collagen fragments as a sign of damage and respond by making more collagen, but this specific ingredient has almost no published human evidence behind it.
Tripeptide-29 is Gly-Pro-Hyp, the most common repeating triplet in collagen, used as a leave-on cosmetic signal peptide.
What it's used for
Applied to the skin in anti-aging serums and creams, marketed for firmness and fine lines.
How does Tripeptide-29 work?
What it does in the body, and where.A fragment of collagen's most common repeating unit, used as a signal rather than a building block.
- 01Collagen is built from repeating tripletsGly-Pro-Hyp is the most common one, so this peptide is essentially a three-letter word cut out of collagen.
- 02Fragments act as damage signalsWound-healing research suggests skin cells respond to collagen fragments by ramping up repair, including new collagen.
- 03Penetration is the open questionWhether enough of a small water-soluble peptide crosses intact skin to matter is unresolved, and this ingredient lacks the fatty tail that helps other cosmetic peptides through.
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.
- Skin firmness and fine lines, the main marketing claimResearch only
At a glance
Four things to know about Tripeptide-29
Evidence
OTC / supplement
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.Topical serum, per product, daily. Used continuously as a daily cosmeticCommunity practice
No study has examined cycling. Cosmetic ingredients of this type are simply used daily until the user stops.
How long does it stay in the body?
The half-life, and where the figure comes from.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.Tripeptide-29 is not injected
It is taken on the skin (topical).
Tripeptide-29 starts at $176.00 across 3 vendors, typically $0.88 – $0.95 per mg.
4 listings, last read Sep 12, 2026. Shipping and card fees are not included.
How do you store it?
Before mixing, and after.Room temperature, out of light. Cap it tight after each use.
Tripeptide-29 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 badly irritated skin
- Known allergy to any ingredient in the finished product
Stop and get help
- A spreading rash or burning where it was applied
- Signs of an allergic reaction
Common effects
- Mild stinging or redness when first used
- Beyond that, little is documented, because little has been published
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Tripeptide-29 approved?
And where the numbers on this page come from.Not as a medicine. Tripeptide-29 is sold without a prescription as a supplement or cosmetic ingredient, which is a different thing from being approved as a drug.
- Approval statusOTC / supplement
- RouteOn the skin (topical)
- CheckedSeptember 2026
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.
- DoseFrom product labeling and published use.
- Vial sizeFrom what vendors typically list; not a recommendation.
- Sources
- Reviewed12 September 2026
What else is like Tripeptide-29?
Others in Skin and cosmetic, side by side.If you're weighing Tripeptide-29, it's worth reading Lipopeptide, GHK-Cu, and Melanotan I (Afamelanotide) in the same class.
A three-amino-acid collagen fragment sold as a signal for firmer skin.
- Dose
- Topical serum, per product
- How often
- Daily
A class label, not one molecule: a peptide with a fatty tail, usually sold for skin and anti-ageing products.
- Dose
- Topical serum, per product
- How often
- Daily
A copper skincare peptide for smoother, firmer, younger-looking skin.
- Dose
- Topical serum, 1-2 pumps
- How often
- Daily
A tanning peptide. The FDA-approved version is an implant for a rare sun-pain condition.
- Dose
- 0.5 up to 1 mg per day (loading phase)
- How often
- Daily then weekly
Guides for this compound
- How to Reconstitute a Peptide
Mix peptide powder with bacteriostatic water, step by step.
- 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
- European Commission CosIng cosmetic ingredient database(2026)Tripeptide-29 is listed as a cosmetic ingredient, which permits its use in leave-on products in the EU. A CosIng listing records that an ingredient may be used in cosmetics. It is not an assessment that the ingredient works.
Last reviewed 12 September 2026