Acetyl Tetrapeptide-5 vs Tripeptide-10 Citrulline
Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research
Also: Eyeseryl, Ac-beta-Ala-His-Ser-His
Acetyl tetrapeptide-5 is a short synthetic peptide sold by Lipotec (now Lubrizol) as Eyeseryl, made for eye creams that target under-eye puffiness. The pitch is that it reduces fluid leaking into the tissue under the eyes. It is a cosmetic ingredient, and nearly all of the human data comes from the company that sells it.
Also: Decorinyl, Decorin-like tetrapeptide
Tripeptide-10 citrulline, sold as Decorinyl, is a small synthetic peptide (four residues, despite the name) designed by the Spanish ingredient maker Lipotec to mimic decorin, a protein that keeps collagen fibers neat and evenly sized. The pitch is better collagen, not more collagen. It is a cosmetic ingredient, not an FDA-approved drug, and almost all of the evidence comes from the company that makes it.
Key Comparison Insights
- Both peptides belong to the Skin & Hair category, suggesting similar primary applications.
Detailed Comparison
| Attribute | Acetyl Tetrapeptide-5 | Tripeptide-10 Citrulline |
|---|---|---|
| Category | Skin & Hair | Skin & Hair |
| FDA Status | Not FDA Approved | Not FDA Approved |
| Clinical Status | Pre I II III IV FDA | Pre I II III IV FDA |
| Mechanism of Action | The peptide is acetyl-beta-alanine-histidine-serine-histidine. The manufacturer's lab work claims three effects: it reduces vascular permeability (less fluid seeping out of small blood vessels, tested in an endothelial cell model), it inhibits glycation (sugar damage to proteins like collagen), and it has some ACE-inhibiting activity that is linked to fluid balance. All of that is in vitro and company-generated. An important reality check: under-eye bags have several causes, and a lot of them in older adults come from fat pads pushing forward and loose skin, not fluid. A peptide aimed at fluid cannot touch fat-pad bags, so even in the best case it fits morning puffiness better than structural eye bags. | Decorin sits on collagen fibrils and controls how thick they grow and how tightly they pack. With age, decorin activity drops, and collagen fibers become uneven and disorganized, which is part of why older skin loses suppleness. Lipotec researchers took the two short sequences decorin uses to grab collagen, built a library of tetrapeptides around them, and screened them in a test-tube collagen assembly assay. The winner, tripeptide-10 citrulline, made fibrils thinner and more uniform in that assay. The idea is that a well-organized collagen network is more cohesive and supple. Whether a topical cream delivers enough peptide to the dermis to do this in real skin has not been independently shown. |
| Common Dosing | 1% of the Eyeseryl solution in an eye cream Twice daily | Around 0.01% peptide in a finished product Once or twice daily |
| Administration | Topical (eye creams, gels, serums) | Topical (serums, creams) |
| Typical Duration | 28-60 days in manufacturer studies; ongoing use to maintain any effect | Studies ran 2 months (60 days); ongoing use for maintained effects |
| Best Time to Take | Morning and evening, gently patted under the eyes | Morning and/or evening skincare routine |
Possible Side Effects May vary by individual |
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| Research Summary | We could not find an independent, peer-reviewed clinical trial of acetyl tetrapeptide-5. The evidence is manufacturer data reported in trade publications. Lipotec's best-known study used a 1% Eyeseryl cream on one eye and placebo on the other in male volunteers aged 30 to 65, twice daily for 28 days, and reported about a 30% reduction in under-eye puffiness volume, with most volunteers rating it positively. Another supplier document describes a 60-day study in 20 women using a cream with a very low peptide level, scored from photos by a dermatologist. Other summaries quote different numbers (17% to 21%) from studies we could not trace to an original paper. The studies differ in concentration, sex, length and how puffiness was measured, so they cannot be pooled. Independent ingredient databases rate the evidence as limited for exactly this reason. Bottom line: plausible for mild fluid puffiness, cheap to try in an eye cream, but not a fix for true eye bags and not backed by independent trials. | The founding paper is Puig, Garcia Anton and Mangues (Lipotec) in the Journal of Cosmetic Science, 2008, which describes the in vitro fibrillogenesis screen. Trade press reporting of the same company work described a 0.01 percent formula applied for two months that made collagen fibers more uniform in a handful of volunteers, and a placebo comparison (22 women on peptide, 21 on placebo) reporting a 54 percent rise in suppleness. Those numbers come from the manufacturer and are not easy to check against full published data. The one independent-looking human trial is Raikou and colleagues, Journal of Cosmetic Dermatology 2017: 24 volunteers split into four groups (combination with acetyl hexapeptide-3, each peptide alone, or neither) for 60 days, with some statistically significant differences in wrinkle microtopography and water loss. Six people per group is very small, and the authors themselves could not explain any synergy. Fair summary: a clever design with real in vitro logic, and thin human data. |
Frequently Asked Questions: Acetyl Tetrapeptide-5 vs Tripeptide-10 Citrulline
What is the difference between Acetyl Tetrapeptide-5 and Tripeptide-10 Citrulline?
Acetyl Tetrapeptide-5 is a skin & hair peptide that acetyl tetrapeptide-5 is a short synthetic peptide sold by lipotec (now lubrizol) as eyeseryl, made for eye creams that target under-eye puffiness. the pitch is that it reduces fluid leaking into the tissue under the eyes. it is a cosmetic ingredient, and nearly all of the human data comes from the company that sells it. Tripeptide-10 Citrulline is a skin & hair peptide that tripeptide-10 citrulline, sold as decorinyl, is a small synthetic peptide (four residues, despite the name) designed by the spanish ingredient maker lipotec to mimic decorin, a protein that keeps collagen fibers neat and evenly sized. the pitch is better collagen, not more collagen. it is a cosmetic ingredient, not an fda-approved drug, and almost all of the evidence comes from the company that makes it. The main differences lie in their mechanisms of action and clinical applications.
Which is better, Acetyl Tetrapeptide-5 or Tripeptide-10 Citrulline?
Neither is universally "better" - the choice depends on your specific goals. Acetyl Tetrapeptide-5 is typically used for skin & hair purposes, while Tripeptide-10 Citrulline is used for skin & hair. Always consult with a healthcare provider to determine which may be appropriate for your situation.
Can Acetyl Tetrapeptide-5 and Tripeptide-10 Citrulline be used together?
Some peptide protocols combine multiple compounds for synergistic effects. However, using Acetyl Tetrapeptide-5 and Tripeptide-10 Citrulline together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.