How many peptides are in The Ordinary Multi-Peptide Serum for Hair Density?

Two: biotinoyl tripeptide-1 and acetyl tetrapeptide-3, at positions six and seven of a thirty-six-ingredient declaration. The name is accurate in the plural sense — there is more than one — but a reader expecting a long peptide list will find the rest of the formula is plant extracts, amino acids, minerals, a stimulant and the usual solvents and thickeners.

What are REDENSYL, Procapil, CAPIXYL, BAICAPIL and AnaGain?

Supplier trade names for ingredient blends, and none of them may appear on a US ingredient list under 21 CFR 701.3(c). Their components are declared individually, so the mapping is checkable on the label: Procapil is biotinoyl tripeptide-1 with apigenin and oleanolic acid, CAPIXYL is acetyl tetrapeptide-3 with red clover extract, REDENSYL includes larch wood and green tea extracts with glycine and zinc chloride, BAICAPIL is a three-extract blend, and AnaGain is pea sprout extract. Five marketing names resolve to two peptides and a set of botanicals.

Why is caffeine listed above the peptides?

Because ingredients above 1 percent must be declared in descending order of predominance under 21 CFR 701.3(a). Caffeine sits at position five and both peptides after it. Below the 1 percent line order stops being required to mean anything, so this does not prove a precise ratio, but the sequence is consistent with caffeine being present in the larger quantity — and caffeine is also the ingredient in the formula with by far the largest published research file.

What does the research on caffeine for hair loss show?

Fifty-one PubMed records and seven randomized controlled trials as of 2026-09-16, which is a substantially larger file than either peptide in this bottle. The largest is a 210-man, six-month non-inferiority study in which a 0.2 percent caffeine liquid produced a 10.59 percent improvement in anagen ratio against 11.68 percent for 5 percent minoxidil. Two limitations are in the paper itself: it was open-label with no placebo arm, and it was funded by the company that sells the tested caffeine product, with one author an employee and one a consultant.

What is published about biotinoyl tripeptide-1?

Nothing under its own name. A PubMed search for the INCI name on 2026-09-16 returned zero records, reproducing the count in our separate evidence entry for the molecule. Six records exist under Procapil, the trade name of the three-ingredient blend it is sold in, and the largest of those is an unrandomised, unblinded comparison against platelet-rich plasma whose outcome was a satisfaction questionnaire. The peptide has never been tested on its own.

What is published about acetyl tetrapeptide-3?

One record. It is a twenty-four-week randomized trial against minoxidil in a small group, with no placebo arm and two other actives in the tested product, so the peptide's own contribution was not isolated. Our evidence entry for the molecule sets out the design in full. For scale, minoxidil has hundreds of records in androgenetic alopecia and dozens of randomized trials.

Has Peptide Glow Journal tested this serum?

No. The page checks the named technologies in this scalp serum — two peptides and a caffeine among them — against the label and against each ingredient's published trials. We have not run our six-week, two-tester assessment on it, so nothing here reports what it does to hair density. The page describes the formula, not a result.

The Ordinary Multi-Peptide Serum for Hair Density: Two Peptides, and Caffeine Above Both

Thirty-six ingredients, five named technologies, and exactly two peptides — listed after caffeine. The ingredient with the largest research file in the bottle is the one not in the product name.

The Ordinary publishes its full ingredient list and names the supplier technologies in its formula, which is unusually good source material — most brands do one or the other. Putting the two documents side by side answers a question the package cannot: in a serum named for peptides, how much of it is peptides? The brand's lash and brow serum shares both of this formula's peptides, one of them under a different supplier name — that lash formula adds two more peptides and lists all four above caffeine.

Five technologies, two peptides

The marketing names six things: REDENSYL, AnaGain, Procapil, CAPIXYL, BAICAPIL and high-solubility caffeine. None of the first five appears in the ingredient declaration, because under 21 CFR 701.3(c) an ingredient must be declared by its established name and a supplier's blend name is not one. Their components are listed individually, so the mapping can be verified against the label rather than taken on trust.

Marketing name	Declared components on the label	Peptide?
REDENSYL	Larix Europaea Wood Extract · Camellia Sinensis Leaf Extract · Glycine · Zinc Chloride	no
AnaGain	Pisum Sativum (pea) Extract	no
Procapil	Biotinoyl Tripeptide-1 · Apigenin · Oleanolic Acid	yes
CAPIXYL	Acetyl Tetrapeptide-3 · Trifolium Pratense (red clover) Flower Extract	yes
BAICAPIL	Scutellaria Baicalensis Root · Triticum Vulgare Germ · Glycine Soja Germ Extracts	no
High-solubility caffeine	Caffeine	no

Two of thirty-six declared ingredients are peptides. They sit at positions 6 and 7 — directly after caffeine at position 5.

That ordering is worth a sentence of care. 21 CFR 701.3(a) requires descending order of predominance above 1 percent, and 701.3(f)(2) releases everything at or below 1 percent from any order at all. So caffeine appearing ahead of both peptides is consistent with there being more of it, without proving a ratio. What it is not consistent with is the intuition the product name creates, that peptides are the leading active in the bottle.

What is published about each thing in it

Counts run through NCBI E-utilities on 2026-09-16, reproducible by anyone:

Ingredient or technology	PubMed records	What those records are
Caffeine (with alopecia or hair growth)	51, incl. 7 RCTs	Human trials of caffeine shampoos, liquids and blends
Procapil (trade name)	6	Blend studies; largest is unrandomised, with a questionnaire outcome
Biotinoyl tripeptide-1 (INCI name)	0	—
REDENSYL (trade name)	5	Multi-ingredient product studies and reviews
AnaGain (trade name)	4	Includes one pea-sprout-extract clinical short communication
Acetyl tetrapeptide-3 (INCI name)	1	One 24-week trial vs minoxidil, no placebo, three actives
CAPIXYL (trade name)	1	—
BAICAPIL (trade name)	1	A review, not a study

Two patterns run through the whole right-hand column.

The peptides have almost nothing under their own names. Biotinoyl tripeptide-1 returns zero — the finding our evidence entry for the molecule is built on, reproduced today. Acetyl tetrapeptide-3 returns one record, a trial with no placebo arm and three actives in the bottle. Neither peptide has ever been tested alone.

Every trade-name record is a study of a commercial product, not of an ingredient. The titles say so: a rosemary-and-Redensyl hair product, a REGENDIL-infused product, topical Procapil with platelet-rich plasma against topical Redensyl and saw palmetto, a "topical active blend". A blend beating a vehicle tells you the blend did something; it cannot tell you which of six ingredients did it. That is the same structural problem our hair-growth evidence hub documents across this entire ingredient class.

The largest trial in the bottle belongs to the caffeine

Dhurat and colleagues (Skin Pharmacology and Physiology, 2017) randomised 210 men with androgenetic alopecia to a 0.2% caffeine topical liquid or 5% minoxidil solution for six months, with the proportion of anagen hairs on frontal and occipital trichogram as the primary endpoint. Caffeine improved the anagen ratio by 10.59%, minoxidil by 11.68% — a difference of 1.09% — and the authors concluded non-inferiority, reported against the CONSORT 2010 extension for non-inferiority trials.

Two things in the paper limit what that means, and both are stated in it. It was open-label with no placebo arm: the comparator was an active drug, which the authors defend as more appropriate than placebo against an established standard, but it means the trial cannot separate either product from expectation. And it was funded by Dr. Kurt Wolff GmbH & Co. KG, which markets the tested liquid as Alpecin; one author is a company employee and another a paid consultant.

So the ingredient with the largest and most conventionally designed evidence file in this serum is caffeine — the one ingredient in the formula that is not a peptide and not in the product name. Whether the 0.2 percent concentration studied bears any relation to the amount here is not disclosed, and cannot be, for the reasons our peptide serum page sets out.

What the published formula shows

It establishes an unusually transparent brand: the full list is published, the technologies are named, and the mapping between them holds up against the label. It establishes two peptides, both below the 1 percent line, both with essentially no literature under their own names. It establishes a caffeine with a real trial record behind it, at an undisclosed concentration, listed above the peptides.

It does not establish what six months of using this serum does to anyone's hair, and we make no claim about that — we have not tested it. What a published formula can show is which of its ingredients have been studied and how, and in this bottle the answer is not the one the name implies.

Sources

The Ordinary, Multi-Peptide Serum for Hair Density — published ingredient declaration and named technologies, theordinary.com, read 2026-09-16.
21 CFR 701.3, Designation of ingredients — eCFR, paragraphs (a), (c) and (f)(2), read 2026-09-16.
PubMed record counts via NCBI E-utilities, run 2026-09-16.
Dhurat R, Chitallia J, May TW, Jayaraaman AM, Madhukara J, Anandan S, Vaidya P, Klenk A. An Open-Label Randomized Multicenter Study Assessing the Noninferiority of a Caffeine-Based Topical Liquid 0.2% versus Minoxidil 5% Solution in Male Androgenetic Alopecia. Skin Pharmacol Physiol 2017;30(6):298–305 — PubMed 29055953, full text and disclosure statement read at PMC5804833.