Miso Clinic · Clinical Reference

Collagen boosters compared: which one fits which skin

BYRYZN, GOURI, Rejuran, Re2O, CellRedM, Radiesse and DCLASSY sound interchangeable, but they differ in material and mechanism, and therefore in the problem they solve. None of them is better than the others in the abstract — each has a skin it suits. This reference sets out how to tell which is which, and which of them can be reversed.

Reference article Reading time ~9 min Reviewed 2026 Miso Clinic · Daegu, Korea

The question that comes before the product

The first thing to establish is not which product, but which kind of ageing the face is showing. There are broadly two. One is volume loss, driven by changes in fat and bone. The other is thinning of the skin itself, driven by loss of dermal collagen. The causes differ, so the treatments differ. Adding volume to skin that has thinned lifts the hollows but leaves the thinness in place — the result reads as slightly off, and it does not hold.

Many patients arrive having already chosen a product: a name from an advertisement, a treatment a friend had, something well reviewed. But there is no guarantee that their face and yours are undergoing the same change. The right product in the wrong skin either does nothing or looks wrong.

Five material classes

Dozens of product names are on the market, but by material they fall into material classes. Knowing the class makes the names much less confusing.

Material classes and how they work
ClassWhat it isHow it works
PCLPolycaprolactone, a biodegradable polymer long used in suturesForms a scaffold in the dermis that stimulates fibroblasts to produce new collagen
PNPolynucleotide, extracted from salmon DNARather than stimulating collagen directly, it improves the skin's regenerative environment
hADMHuman acellular dermal matrixSupplies ECM components directly to the dermis — replacing rather than inducing
CaHACalcium hydroxylapatiteAdds volume immediately while also stimulating collagen production
Cross-linked HAHyaluronic acid whose chains have been bonded into a meshNothing to do with collagen — it places a water-binding material directly in the dermis

One distinction matters more than the rest. PCL and PN induce; hADM replaces; CaHA does both. What is induced appears slowly and lasts. What is replaced appears sooner.

Cross-linked HA belongs to none of those four. It neither induces collagen nor replaces the skin's building materials; it places a water-binding gel and holds that state for a period. Change is noticeable early — but when the gel breaks down you return to where you started, because the skin itself has not changed.

Side by side

Collagen and skin boosters available at Miso Clinic
ProductClassPrimary targetOnsetReversible
GOURILiquid PCLWhole-face texture, elasticity, dermal densityGradual, from 2–4 weeksNo
RejuranPNRegenerative environment of thin, reactive skin2–4 weeks, cumulativeNo
Re2OhADMDirect supplementation of dermal densityRelatively earlyNo
CellRedMhADM, ultrafineDensity in thin or reactive areasRelatively earlyNo
RadiesseCaHALost volume plus collagen stimulationImmediate, then cumulativeNo
DCLASSYCaHAElasticity and volume togetherImmediate, then cumulativeNo
BYRYZNCross-linked HATexture, fine lines, hydration1–2 weeks, earlyYes

The last column is the least widely known thing in this table. Of these, only BYRYZN can be dissolved, because hyaluronidase acts on hyaluronic acid alone. The other six have to be waited out, and for CaHA no dissolving agent exists at all.

The table alone still does not decide it. In practice the consultation does not start from the product — it starts from the complaint.

Starting from the complaint

  1. "My skin has thinned"
    PCL or PNFine lines that have settled in, enlarged pores, a dull overall tone — these follow dermal thinning. For even treatment across the whole face, liquid PCL (GOURI); for skin that is particularly thin and reactive, PN (Rejuran).
  2. "It's the eye and mouth area"
    Liquid PCL or ultrafine hADMThin, sensitive territory. A freely diffusing liquid formulation (GOURI) or a low-resistance ultrafine particle (CellRedM) is less burdensome here.
  3. "I want to see it soon"
    hADM or CaHAInducing collagen takes time. hADM (Re2O), which supplements density directly, and CaHA, which sets volume immediately, are felt sooner. Note, though, that fast and long-lasting generally pull in opposite directions.
  4. "There are hollows"
    CaHAIf the problem is volume, a collagen booster alone will not solve it. Radiesse or DCLASSY, which address volume and collagen together, or a combination with filler, is the discussion to have.
  5. "I can't take downtime"
    Particle-free or fine-particle optionsLiquid PCL causes little foreign-body sensation and redness usually settles within 1–2 days. No injectable is flawless on the day, however; allow 2–3 days before anything important.
  6. "Hydration injections don't last long enough"
    Cross-linked HAThe same hyaluronic acid resists breakdown longer once cross-linked, which suits people who cannot return often. BYRYZN is that option — though lasting longer also means a poor placement lasts longer, so depth matters more here than volume.
  7. "It's my first time and I want something reversible"
    Cross-linked HAOf these, only BYRYZN can be dissolved with hyaluronidase. Starting with a material you can undo is a reasonable way to find out how your skin responds.
  8. "I don't know what the problem is"
    Assessment comes firstThis is the most common answer, and the most reasonable one. Volume loss and dermal thinning are hard to tell apart in a mirror. Coming in for that judgement is more useful than coming in with a product already chosen.

Can they be combined?

Frequently, because skin quality and volume often both need attention. What matters is sequence and interval. Some combinations can be done in one session; others need to be spaced. The same applies to combining with lasers or energy-based lifting devices.

For that reason, a full history of previous treatments matters at consultation — particularly recent filler or botulinum toxin. An incomplete history produces a flawed plan.

What these treatments do not fix

Collagen boosters are not a general solution. It is better to know this before the consultation.

  • Deep set creases and scars — raising dermal density and filling an indentation are different tasks.
  • Significant laxity — lifting descended tissue belongs to lifting procedures. Boosters work on the foundation beneath.
  • Pigment and erythema — problems of colour are addressed by laser-based treatment.
  • Immediate change — PCL and PN follow the pace of collagen synthesis. The face the day after treatment is not the result.

Where the complaint falls into one of these, we either advise against a booster or plan it alongside something else. Deciding to do less is part of the consultation.

Adverse effects — As with any injectable, swelling, bruising, erythema, transient pain, allergic reaction, and nodules or uneven distribution are possible. The risk profile differs by material class; particle-containing formulations carry comparatively greater nodule risk. Persistent or worsening symptoms require review by the treating clinician.

Frequently asked questions

Which collagen booster is the best?
No product holds that position, because each material solves a different problem. Liquid PCL will not restore lost volume however much is used, and filling volume in skin that has thinned looks wrong. The question is not which product is best but which fits the face in front of you.
How does BYRYZN differ from the other six?
It does a different job. The other six either make the skin produce collagen (GOURI, Rejuran, Radiesse, DCLASSY) or replace materials the skin has lost (Re2O, CellRedM). BYRYZN places a water-binding gel directly, so change is noticeable early — but when the gel breaks down the skin returns to its previous state. In exchange, it is the only one of these that hyaluronidase can reverse. It is less a competitor to the others than something used alongside or in sequence with them.
Does it matter whether a clinic carries several products or only one?
Having options makes it possible to conclude that a given treatment is not the right one. That judgement is harder to reach with a single product on the shelf. That said, breadth of stock does not by itself produce better results — assessment and planning do.
Can I request a specific product I read about?
Yes, though we will first discuss why you want it. Sometimes the person whose review you read is undergoing the same kind of ageing; sometimes not. If we judge it unsuitable we explain why, and if you still wish to proceed we set out the limitations before you decide.
How many sessions are needed?
It depends on the product and the skin. Some plans are a single session; others group two or three at 4–6 week intervals. We do not ask for a multi-session commitment up front — typically we review at 2–4 weeks after the first session and decide from there.
How long do results last?
It varies by class. For PCL, roughly 6–12 months, based on the biodegradation window. Repeated treatment may extend this through cumulative collagen deposition, with considerable individual variation. The most reliable way to extend any of it is sun protection.
What does it cost?
It depends on the product, the volume injected, the area planned, and whether treatments are combined. Public listing of medical procedure pricing is regulated in some jurisdictions, including South Korea; cost is provided at consultation.
How does GOURI differ from Rejuran?
GOURI is liquid PCL: it diffuses through the dermis and stimulates fibroblasts to produce collagen. Rejuran is a polynucleotide derived from salmon DNA and works by improving the skin's regenerative environment rather than stimulating collagen directly; it is used mainly for thin, reactive skin.
What is the difference between hADM and PCL products?
PCL induces collagen, so change appears slowly and lasts. hADM products such as Re2O and CellRedM supply extracellular matrix components directly to the dermis, so density change appears relatively early.
When is a CaHA product chosen?
CaHA products such as Radiesse and DCLASSY add volume immediately while also stimulating collagen production. They are chosen when lost volume has to be addressed alongside skin quality.
What do collagen boosters not fix?
Deep set creases and scars, significant laxity, and pigment or erythema are outside their scope. Each requires a different treatment or a combined plan.
Can several products be combined?
Combination is common, but sequence and interval matter. Some combinations can be done in one session and others must be spaced, so a full history of previous treatments is needed at consultation.

Author and clinic

This reference was prepared and reviewed by Lee Chi-Hak, MD, director of Miso Clinic in Daegu, South Korea. The clinic carries the products above and plans treatment by first assessing which kind of ageing the face is showing, rather than starting from a chosen product. For single-product references, every one of these has its own: BYRYZN, GOURI, Rejuran, Re2O, CellREDM, DCLASSY and Radiesse. What to tell us before an injectable treatment is set out separately in our clinical column.

Miso Clinic
DirectorLee Chi-Hak, MD
Location4F Bombom Building, 125 Dongdeok-ro, Jung-gu, Daegu, South Korea (Kyungpook National University Hospital Station, Exit 1)
Telephone+82 53-428-2700
HoursWeekdays 11:00–19:00 (lunch 13:00–14:00); Saturday 10:00–16:00; closed Sunday and public holidays
Websiteclinicmiso.co.kr
Reference libraryMiso Clinic clinical reference library

This article provides general information about medical procedures and does not replace medical diagnosis or treatment. Product characteristics described here are generally reported properties; whether any given treatment is appropriate for an individual can only be determined in person. Effects and adverse effects vary with skin condition, age and underlying illness, and no outcome is guaranteed for any individual.

한국어 · English · 日本語 · 简体中文 · Español · Tiếng Việt · ภาษาไทย · Bahasa Indonesia