Korean Skincare Salmon DNA, From the Label on a Serum to the Line on a Clinic Menu

I'm Dr. Hyunji Kim, director and lead physician at Delphic Clinic in Gangnam, Seoul. My background is Korea University Medical Center, and I'm a member of the Korean Academy of Aesthetic Surgery & Laser Medicine, the Korean Society for Laser Dermatology & Hair and the Korean Filler Society.

Korean skincare salmon DNA comes up often in my consultation room, and one number, about 500 daltons, settles most of the confusion. Salmon DNA is one ingredient family, DNA fragments purified from salmon or trout sperm cells and labelled PDRN or PN. It's sold as serums and masks you apply, and as injections placed into the dermis. Healthy skin keeps out most molecules heavier than about 500 daltons, and these DNA chains are far heavier. So the jar and the needle do different jobs.

Before the details:

• “Salmon DNA” on a Korean label means PDRN or PN. On a clinic menu, “salmon injection” means PDRN injected into the skin.
• Rejuran is a PN product line. Our Rejuran 3cc/6cc listing gives a 2–3 week interval and about 1–3 days of downtime.
• Exosomes, MTS and “nano infusion” are separate things that often sit on the same menu page.
• At Delphic, the doctor performs injections directly, and same-day treatment is possible after the consultation.

What does “salmon DNA” actually mean on a Korean label?

Salmon DNA on a Korean label almost always means PDRN (polydeoxyribonucleotide) or PN (polynucleotide). Both are purified DNA extracted from the sperm cells of salmon or trout. The difference is chain length: PDRN is cut into shorter fragments, PN keeps longer chains.

A 2025 review in Pharmaceutics comparing PN and PDRN describes them as related molecules with different sizes and slightly different behavior in tissue. PN's longer chains hold water and give a gel-like body, which is why PN products tend to feel thicker under the skin. PDRN is the version most research on tissue repair has focused on.

Three more words you'll meet:

• Polynucleotide. Sometimes used for PN specifically, sometimes for the whole family. When a menu says it, ask which one.
• Salmon sperm facial. The same ingredient, described by its source. The wording sounds odd in English, but it refers to the same purified DNA, not to anything raw.
• Salmon injection. Korean clinics' everyday name for a PDRN injection. On our menu it appears as Salmon Injection PDRN 3cc.

Why a serum and a needle aren't two strengths of the same thing

A serum and an injection use the same ingredient family but deliver it to different places. The serum sits on and in the outer layer; the injection places DNA fragments in the dermis, where collagen and the cells that repair skin actually live.

The 500 Dalton rule, described by Bos and Meinardi in Experimental Dermatology in 2000, explains why: molecules much larger than about 500 daltons pass through intact skin poorly. DNA fragments are far larger than that. A salmon DNA serum can still be a moisturizer you like using. It just isn't doing the same job as an injection.

Inside the dermis, PDRN is thought to work partly through adenosine A2A receptors, which influence inflammation and tissue repair. A 2021 review on PDRN and wound healing summarizes this mechanism. That repair angle is why salmon DNA injections are discussed for skin recovering after lasers, for thin, crepey skin, and for fine texture changes.

Which words on a clinic menu point to an injection?

“Is this one a cream or a needle?” is a question I hear in consultation about menu lines. The quickest tell is volume: if a line has “cc” in it, something is going under the skin.

Our Rejuran 3cc/6cc listing gives a recommended interval of 2–3 weeks between sessions and about 1–3 days of downtime. For a short trip, that interval matters more than any other number in the table: one visit usually holds one session, and the next one would land on a later trip. If you're weighing Rejuran against a plain PDRN injection, my longer comparison is in salmon injection or Rejuran.

Exosomes, MTS and nano infusion sit next to salmon DNA on the menu

Exosomes are not salmon DNA. They are tiny vesicles released by cells, used in skincare as a separate category. Our menu lists 5th Generation Exosome Exohealer, and one of its options is combined with MTS.

• MTS (microneedle therapy system): fine needles create short channels so a solution applied afterwards can reach below the surface. It is a delivery method, not an ingredient.
• Nano infusion: a term for devices with very short tips pressed over the skin to help topical products in, usually without bleeding. It isn't on our menu. If you've seen “Korean salmon DNA nano infusion” online, it describes a surface delivery method, closer to a facial than to an injection.
• Juvelook: a different booster that works through a collagen-stimulating material, often listed on the same page as PDRN.

When a menu bundles two of these words, read them as two separate things done in one sitting.

Does your skin need a salmon DNA injection?

The answer depends on which layer the problem lives in. Salmon DNA injections are considered for dermal quality: thin, dull or crepey skin, fine texture, and skin recovering from a laser. Pigment, active acne and sagging usually need something else first.

A few visible signs generally help a doctor place the problem. How the skin creases in a smile, and whether fine lines stay once the face relaxes. Whether there are post-acne marks, and whether they're red, brown or indented. How the skin behaves under a gentle stretch: thin skin tends to wrinkle like tissue paper, while dehydrated skin usually smooths out.

Brown spots point toward toning such as PicoSure; what that kind of treatment can and can't change is in what skin whitening treatment can honestly change. Active acne generally needs to calm down before any injection goes near it, and our menu covers that with options such as LDM in acne mode and the Acne-Clearing packages; red, reactive skin is covered in LDM for reactive skin. Sagging along the jawline points toward a lifting device. None of these is a salmon DNA problem.

Our menu also pairs PDRN with Potenza and with Pico Fraxel in single-session packages. The general logic is that a microneedling or laser session leaves the skin in repair mode, which is where PDRN research has concentrated.

Side effects, and who it doesn't suit

The usual side effects are small raised bumps at the injection points, redness, mild tenderness and pinpoint bruising. These generally settle over hours to a few days, and people vary. Less common are longer-lasting swelling or a bruise that takes a week to fade. Infection and allergic reactions are rare but possible with any injection.

The clinical evidence is still limited in size. A systematic review of polynucleotides in esthetic medicine collects the clinical studies so far, and many of them are small. Treat salmon DNA as a skin-quality treatment, not a lift.

It doesn't suit you, or should wait, if:

• you have a known fish or salmon allergy, or reacted to a PDRN or PN product before (tell the doctor first);
• there's an active acne flare, cold sore or skin infection where the injections would go;
• you're pregnant or breastfeeding, when most doctors postpone elective injections;
• you take blood thinners or bruise easily, which needs a conversation before any needle;
• your main goal is lifting a sagging jawline.

You also don't need to come in for this at all if your skin feels comfortable and you mainly want a little glow. A topical salmon DNA product is a reasonable choice for that, and so is leaving your routine alone.

What should you ask before booking a session on a short trip?

Plan the session around your flight, not the flight around the session. Clinic hours set the frame: we're open Mon–Fri 10:30–21:00 and Sat 10:30–17:00, closed on Sundays.

A short self-check before you message any clinic:

• Which word did I see? Screenshot the product or menu line. PDRN, PN, exosome and Juvelook are different things.
• Am I after a product or a treatment? If it's a product, a clinic visit may not be needed.
• What's bothering me, in one sentence? Dryness, texture, post-laser recovery, pigment or sagging.
• How many days do I have after the session? Bumps and pinpoint bruises can be visible for a day or more. Our Rejuran 3cc/6cc listing says about 1–3 days of downtime.
• Am I flying out soon after? Avoid planning photos or a beach day straight after.
• Anything to declare? Allergies, medicines, pregnancy, recent lasers.

Every treatment on our menu is listed on the Delphic Clinic English site.

If you're planning a Seoul trip, send your travel dates and a screenshot of the salmon DNA product or menu line you saw on WhatsApp, so the 1:1 consultation can start from what you saw. An English interpreter is on site, and the clinic is directly connected to Sinnonhyeon Station Exit 3.