What Does Rejuran Do? Slow Skin Repair, Not Volume or Lift

So what does Rejuran do once it's under your skin, and is it worth planning part of a Seoul trip around an injection whose result you won't see in the mirror that same week?

Rejuran places purified polynucleotide (PN) fragments into the dermis, where they support your skin's own repair: better hydration, finer texture and softer fine lines, building over several weeks and a short series of sessions. It doesn't add volume, and it doesn't lift sagging skin.

Hello, I'm Dr. Hongseok Kim, a board-certified dermatologist with 21 years of clinical experience and the medical director of VOS Dermatology Clinic in Gangnam.

I do every consultation and every procedure myself, so the person deciding whether Rejuran suits your concern is the one holding the syringe. If needles are what you dread, we offer nitrous-oxide sedation, used in over 5,700 cases here. And a medical interpreter for your language is provided at no extra charge.

If you can't tell whether your concern is about the skin's texture or about lost volume, send one daylight photo of your face without makeup on WhatsApp and point to the area that bothers you most. The consult on WhatsApp is free, and a single photo is enough to start the conversation.

Is Rejuran really salmon DNA that turns into new skin?

Half of that is true. The PN in Rejuran is purified from salmon DNA, but it never becomes your DNA and it doesn't turn into skin. The fragments sit in the dermis for a while, hold water, act as a scaffold and nudge fibroblasts, the cells that make collagen, to work harder. Then your body breaks them down.

A claim you'll see repeated online, that fish DNA rebuilds your face, makes Rejuran sound like a transplant. It works more like feeding a lawn: whatever grows back is your own grass, and it grows at the speed grass grows. That is why the change shows over weeks, long after the injection marks have gone.

The published reviews of polynucleotides describe the same picture: better hydration, elasticity and fine texture, with modest changes that build across sessions. They don't describe new volume or a lifted jawline, and nobody offering you Rejuran should promise either.

Risks and side effects to know

On our own price list, Rejuran Healer is described as suited to sensitive skin, redness and a compromised skin barrier. That tells you where it earns its place: skin that is thin, reactive or tired at the surface, more than skin that has dropped. Results vary by person.

What does Rejuran do that a filler doesn't?

Filler occupies space. It sits under a hollow or a fold, and you see the difference the same day. Rejuran is thin, spreads through the dermis, and changes the quality of the skin rather than the shape underneath it.

Here's a test you can do in a mirror tonight. Turn your face toward a window and look at the area that bothers you. If you see roughness, dullness, crepe-like fine lines or makeup settling into creases, that's the layer Rejuran reaches. If you see a shadow, a groove under the eye or a cheek that has flattened, that's volume, and Rejuran won't fill it.

Sagging along the jaw is a third problem again. That usually calls for a lifting device such as Ultherapy PRIME, which works well below the dermis. If volume turns out to be what you're after, my comparison of how Korean fillers differ from Juvederm will help you more than anything about Rejuran.

Why can't a Rejuran cream do the same job?

The molecule is too big to get through. Intact skin lets in very little above roughly 500 daltons, and PN chains are many times larger than that. A Rejuran-branded serum can moisturize the surface, but it can't put PN into the dermis the way a needle does. I went through the numbers in why the 500-dalton limit decides what Rejuran skincare can do.

Healer, Eye and HB: which area each one is for

Rejuran comes in versions, and the version decides where it goes. On our menu, the three are used like this:

The amount matters as much as the type. I dose each area to what that skin needs, never more and never less, so two people asking for Rejuran on the face can leave with different plans. Type, area and the number of millilitres are also what move the cost; I covered those factors in what decides the cost of Rejuran in Korea.

How long until you see a change, and how many sessions?

The injection bumps usually flatten within about a day. Skin often looks a little more hydrated within the first couple of weeks, and the change in texture and fine lines shows over the weeks after that. Rejuran is commonly given as a short series, often around three sessions two to four weeks apart, and the result is judged after the series.

That timeline is the real planning problem for a visitor. A week in Seoul fits one session. A stay of three weeks or more can fit two. One session is a start, and it helps to know that before you build a flight around it.

Worth knowing: Judge a Rejuran session at about four weeks, in daylight, in the same mirror you used before it. The first few days are the worst time to look, because the bumps and slight swelling cover the very texture you're trying to assess.

On a short trip, put the session early. We're open Saturdays from 10:00 to 16:00 and closed on Wednesdays, Sundays and public holidays, so check your dates against that before you fix the day. A session two or three days before your flight gives the marks time to settle; one on your last afternoon means flying with them.

Bumps, bruising and the fish-allergy question

Small raised bumps along the injection points are expected for the first day, sometimes a little longer. Redness and tenderness usually fade within hours to a day. Pinpoint bruises can appear and may take up to a week to clear. Less often, a small lump lasts longer, and rarely an injection site becomes infected.

How visible the change is, and how quickly it comes, differs from one person to the next.

As general medicine, these are reasons to wait or skip it:

Infection and bruising: what to watch for

• an allergy to fish or salmon-derived ingredients
• an active infection, acne flare or cold sore where the injections would go
• pregnancy or breastfeeding
• isotretinoin in recent months, or a recent laser or peel on the same area
• blood thinners or a bleeding tendency, which raise the chance of bruising and need discussing first

Two things matter more for safety than the brand name. The product should be genuine, and I treat that as a medical question, not a marketing one. And what reaches your skin should be clean: we use a 5μm filter syringe that blocks micro-particles such as ampoule glass shards.

If something looks wrong after you're home, the signs that need a doctor that same day are heat, spreading redness, pus, worsening pain or fever after the first two days. For anything short of that, such as a bump that hasn't settled, send a photo on WhatsApp; my team replies there in English.

If your plan hinges on a flight, send your arrival and departure dates on WhatsApp along with anything done to your face in the last six months, such as a laser, a peel or another injection. Then ask which day of your stay the session should fall on.

How I approach Rejuran for a visitor

Every plan starts with a skin analysis, and I choose the treatment or combination for your face; you won't be handed a fixed package. With Rejuran, the question that analysis answers is which layer the problem lives in. If it's the surface, Rejuran fits. If it's volume or laxity, I'll say so and suggest what would reach it.

Say you're 41, you live in Dubai, you spend most of the year in air-conditioning, and by afternoon your cheeks look rough and dull, with fine lines under the eyes but no real hollows. That's a face where I'd consider Rejuran Healer on the cheeks and Rejuran Eye under the eyes. I'd also tell you that one session on a seven-day trip is the first step of a series, and the fuller change comes later.

Now change one detail: the under-eye has a groove that casts a shadow. Rejuran alone won't erase that, and I'd tell you before you spent anything on it.

For the injections themselves, numbing cream usually takes the edge off, and the sting comes in short bursts across the face. If that still sounds like too much, nitrous-oxide sedation is worth asking about.

What should you ask any clinic before the injection?

In short, it doesn't have to be us. Wherever you book, these answers tell you most of what you need to know:

• Is the vial genuine and sealed, and will it be opened in front of you?
• Who examines you, and is that the same doctor who injects?
• Which type of Rejuran goes where, and how many millilitres in each area?
• Is the price the same whatever your nationality, and what does the quote include? I listed the lines to look for in what a Rejuran injection quote should count.
• How do you reach the clinic after you fly home, and in which language?
• Is a medical interpreter available, and does it cost extra?

At VOS, the listed price is the same for every nationality.

Before you message us

Where I stand: Rejuran is worth your time when the complaint is the skin itself, its dryness, its roughness, the fine lines makeup settles into. For a hollow or a loosening jaw I'd point you to something else, and I'd rather say that before you book a flight. You can take as long as you like to decide; a first message commits you to nothing.

What decides your plan in the end is how thin your skin is and which layer the change sits in. The consult on WhatsApp is free: send a daylight photo from the front and one from the side, the dates you'll be in Seoul, and ask whether what you're seeing is a texture problem Rejuran can reach or a volume problem it can't. If you're ready to book, ask in the same chat how the deposit and payment work.

Open a WhatsApp chat with VOS

— Dr. Hongseok Kim, Board-certified dermatologist, Medical Director, VOS Dermatology Clinic

Results, timing and recovery vary from person to person. This article is general information from VOS Dermatology Clinic and does not replace an in-person consultation. Any prices mentioned are from the clinic’s official price list (KRW, before VAT) and may change.