Rejuran Injection in Singapore: Rejuran Healer, polynucleotides, sessions and risks

The basics

What Rejuran is: a polynucleotide, not a filler

Rejuran is a Korean brand of injectable polynucleotide (PN), made by PharmaResearch. Polynucleotides are chains of DNA fragments purified from the sperm DNA of salmon trout or chum salmon. A 2024 review describes the purified material as over 95% active substance, with the remaining peptides and proteins inactivated. The aim is not to add volume but to give the skin a material it can use: the fragments are thought to form a water-holding, scaffold-like gel in the dermis and to send repair signals to skin cells.

In clinics, 'Rejuran' is often used loosely for any salmon DNA treatment, and the terms 'PDRN' and 'PN' are used interchangeably. A 2025 review proposed keeping 'PDRN' for shorter chains below 1,500 kDa and 'PN' for longer chains at or above that size, because chain length changes how the material behaves. Products under one brand name can also differ, so it is fair to ask exactly what is being used, and whether it will be injected or applied to the surface of the skin.

The main injectable version is known as Rejuran Healer, and the brand also markets versions aimed at the eye area and at scars. All injectable versions are given by a doctor. A needle-free 'Rejuran facial' is a different thing altogether: a cosmetic product applied to the skin, explained further down this page.

Mechanism

How polynucleotides are thought to work

Research on PDRN began in wound healing rather than aesthetics. A 2017 pharmacology review describes two main actions. PDRN binds adenosine A2A receptors, which are involved in tissue repair and in damping inflammation, and it supplies nucleotides that cells can reuse to build new DNA, known as the salvage pathway. It has been used for wounds, diabetic foot ulcers and joint problems.

Longer polynucleotide chains hold water and form a porous, gel-like matrix in the skin. In aesthetic use, this is thought to be why people describe their skin as more hydrated and resilient, with finer texture, over a course of treatment. Increased fibroblast activity and collagen production are part of the proposed mechanism, but much of the support for this comes from laboratory work rather than from measurements in people.

In plain terms, PN is a supportive, repair-oriented treatment for skin quality. It does not lift sagging skin, fill a hollow or reshape the face, and its effect builds gradually over weeks rather than on the day.

Compared

Rejuran vs HA skin boosters and Profhilo

HA skin boosters use soft hyaluronic acid placed as microdroplets in the dermis; they bind water and improve hydration and fine lines. Profhilo is a different hyaluronic acid product: a very fluid gel injected at five points on each side of the face that then spreads under the skin. Both are built on hyaluronic acid. Rejuran is built on DNA fragments and, like an HA booster, is placed as many small droplets.

In a randomised, double-blind split-face trial of 27 people in Korea, a PN product was injected around one eye and a non-cross-linked HA product around the other, three times two weeks apart. Overall improvement scores were similar on both sides. Roughness and pore volume improved more on the PN side, and improvement rates for elasticity and hydration were higher with PN; no serious adverse events were reported. This is one small study, and no head-to-head trial of Rejuran against Profhilo has been published.

One practical difference is reversibility. Hyaluronic acid products can be broken down with the enzyme hyaluronidase if needed. PN is not hyaluronic acid, so hyaluronidase does not dissolve it; the body clears it over time. Because PN is placed in very small amounts and does not bulk up tissue, this is seldom an issue, but it is worth knowing.

PN adds very little volume, so it is sometimes discussed for skin quality in people who want to avoid adding more hyaluronic acid. It is not a treatment for an overfilled face, though: if earlier filler is making the face look heavy, that is assessed and dealt with first.

Two routes

Rejuran injection in Singapore vs the needle-free facial

Injected PN is a medical procedure, and in Singapore it must be performed by a doctor. The product is placed about 1 to 2 mm deep, as microdroplets of roughly 0.01 to 0.05 mL spaced about 1 cm apart, by hand with a fine needle, with an injector device or by cannula. This puts the material into the dermis, which is where the clinical studies placed it.

Needle-free 'Rejuran facials' use cosmetic-grade PDRN products applied to the skin, sometimes with a device to help delivery. At SkinRev Lab, the Rejuran® PDRN Facial uses cosmetic-grade c-PDRN with Meso Touch transdermal technology and is performed by aesthetic therapists. There are no needles and little or no recovery time, and it can be repeated comfortably.

The two are not interchangeable. Intact skin is a strong barrier: molecules larger than about 500 daltons pass through it poorly, and DNA fragments are far larger than that. A topical treatment therefore works closer to the surface and at a lower concentration, and change is gentler and builds across a course. The published studies on polynucleotides used injections, so their results cannot be transferred directly to facials.

A sensible way to choose: the facial suits people who want better hydration and comfort without needles, or maintenance between medical treatments. An injection suits people who want the effect that was studied in trials and can accept a day or two of visible bumps.

Sessions

How many sessions, and how long the effect lasts

There is no single protocol. A 2024 review of skin boosters describes standard Korean practice as 2 mL of PN injected across the face every three to four weeks, for three to four sessions. A survey of 235 Korean dermatologists found that 88% used PN injections, chiefly for fine lines on the face and around the eyes, commonly as three sessions four weeks apart, and 79% combined them with energy-based devices.

The same review cites a European consensus suggesting that, after three sessions three weeks apart, effects typically last six to 12 months. These are typical patterns, not promises: how long any change lasts depends on your skin, age, sun exposure and what else you do for it.

In practice, the number of sessions depends on what is being treated and how your skin responds, and any maintenance is decided at review rather than fixed in advance. Change builds over weeks, so judge it in photographs taken in the same light rather than in the mirror the next morning. PN is often combined with lasers, radiofrequency microneedling or HA boosters; the order and spacing should be planned by the treating doctor, and every clinic should know what you have had and when.

Evidence

What the studies show, and their limits

A 2025 systematic review found nine studies of polynucleotide injections, covering 219 patients, all of low to moderate quality. Results for wrinkles, texture and elasticity were promising and side effects were mild and short-lived, but the authors called for more rigorous trials before firm conclusions are drawn.

For acne scars, a small double-blind study randomised 20 women with moderate to severe atrophic scars to a highly purified PN product or to saline. Only the PN group improved significantly at one and three months. Twenty people is a very small trial, and PN is one of several options for scars rather than a replacement for resurfacing, subcision or energy-based treatment.

On safety, an international expert panel reported no published cases of granuloma or vascular occlusion with PN to date, while noting that the evidence base remains limited. Several panel members advise the manufacturer and some authors are employed by it. That does not make the findings wrong, but it is worth bearing in mind with any claim about a branded product, including the ones on this page.

Recovery

Downtime, aftercare and what it feels like

Numbing cream is usually applied for 20 to 30 minutes first. The injections feel like a series of small pricks; thin skin under the eyes and on the neck is more sensitive. Afterwards the skin shows a grid of small raised bumps with some redness, which usually settle within a day or two, and a little longer under the eyes. Bruising is possible, especially around the eyes, and can take about a week to fade.

Avoid make-up for the rest of the day, and saunas, strenuous exercise and facial treatments for a day or two. Use gentle skincare and sunscreen. Do not book an injection the day before an important event. Seek help at once if, after any facial injection, the skin nearby turns pale, white, blotchy or dusky, pain keeps increasing, or your vision changes: contact the treating clinic immediately or go to an emergency department.

A session usually takes 30 to 45 minutes including numbing. Before booking, tell the doctor about recent filler, toxin, laser or peels, any history of cold sores, and any medicines or supplements that make you bruise easily. If the eye area is being treated, plan for possible bruising that make-up may not fully cover for several days.

Safety

Risks, fish allergy and who it does not suit

Expected effects are bumps, redness, swelling, tenderness and bruising at the injection points. Infection is uncommon but possible with any injection. Any injection into the face also carries a rare risk of entering a blood vessel; the reported safety record of PN is reassuring, but careful technique and knowledge of anatomy still matter, particularly around the eyes and nose.

Fish allergy is a common question. PN is purified from salmon DNA, and fish allergy is usually triggered by fish proteins, which purification is designed to remove or inactivate. Even so, we found no published studies of PN injections in people with a fish allergy. If you have a known fish or seafood allergy, especially a severe one, tell the doctor before anything is injected; the cautious choice is usually a different type of booster.

Who it does not suit, or needs discussion first:

• Not advised: pregnancy or breastfeeding; active infection, cold sores, an eczema flare or inflamed acne in the area; known allergy to any ingredient.
• Discuss first: fish or seafood allergy, autoimmune disease, a tendency to keloid scars, blood thinners or a bleeding tendency, and any recent filler, laser or peel in the same area.
• Not the right tool: hollows, a flat cheekbone or heavy jowls, which need filler, a biostimulator, lifting or a surgeon's opinion; pigmentation, which usually needs laser or topical treatment.
• See a dermatologist first if the main problem is a skin disease such as rosacea, eczema or active acne.
• Poor timing: anyone who cannot accept a day or two of visible bumps before an event.

Alternatives

Alternatives to consider

If hydration and fine lines are the main concern, an HA skin booster or a bio-remodelling HA injection such as Profhilo may suit. If you want gradual collagen support, a poly-D,L-lactic acid (PDLLA) booster may be discussed. For texture, enlarged pores and acne scars, lasers, radiofrequency microneedling or resurfacing usually do more than any booster on its own.

For lost volume or sagging, a booster is the wrong tool: filler, a collagen biostimulator or energy-based lifting are the relevant conversations, and a plastic surgeon's opinion where there is excess skin. If you are not ready for injections, a needle-free facial, daily sunscreen and a retinoid are a reasonable start. Choosing to wait, or to have no treatment, is also valid.

If you are unsure what your skin needs, it helps to separate three questions: is the problem the skin surface, the skin itself, or the structure underneath? Surface concerns respond to skincare, peels and facials; skin quality to boosters and some lasers; structure to filler, biostimulators or lifting. A PN booster answers only the middle question.

At SkinRev Lab

What happens at SkinRev Lab

Injectable skin boosters, including PN boosters, are performed by Dr Sin Yong after a consultation, at SkinRev Lab, #B1-28 CityLink Mall, 1 Raffles Link, linked underground to City Hall and Esplanade MRT, open daily 11am to 8pm (WhatsApp +65 8266 9585), or at IN Eternity Clinic, 9 Scotts Road, #12-01 Pacific Plaza, beside Orchard MRT, Monday to Saturday 11am to 8pm (WhatsApp SkinRev Lab on +65 8266 9585 or IN Eternity Clinic on +65 8815 3008).

He looks at skin quality, thickness and sensitivity, pigmentation, laxity and any earlier injectables, asks about allergies including fish and seafood, and tells you plainly whether a PN booster fits your concern, whether another booster or treatment makes more sense, or whether no treatment is the right answer. Injectable treatment is priced at consultation. Our pages do not commit to a brand, so ask which product would be used.

The needle-free Rejuran® PDRN Facial is a separate, non-medical treatment at SkinRev Lab, CityLink Mall, performed by aesthetic therapists, at S$128 to S$348 per session before GST depending on the tier. The price guide sets out the tiers and how they differ from injections. A facial is not a substitute for a doctor's assessment if you have a medical skin concern.

Sources

References & sources

1. Squadrito F, Bitto A, Irrera N, Pizzino G, Pallio G, Minutoli L, Altavilla D. Pharmacological activity and clinical use of PDRN. Front Pharmacol. 2017;8:224. PMID 28491036.
2. Marques C, Porcello A, Cerrano M, et al. From polydeoxyribonucleotides (PDRNs) to polynucleotides (PNs): bridging the gap between scientific definitions, molecular insights, and clinical applications of multifunctional biomolecules. Biomolecules. 2025;15(1):148. PMID 39858543.
3. Rho NK, Kim HS, Kim SY, Lee W. Injectable 'skin boosters' in aging skin rejuvenation: a current overview. Arch Plast Surg. 2024;51(6):528-541. PMID 39544509.
4. Lee YJ, Kim HT, Lee YJ, et al. Comparison of the effects of polynucleotide and hyaluronic acid fillers on periocular rejuvenation: a randomized, double-blind, split-face trial. J Dermatolog Treat. 2022;33(1):254-260. PMID 32248707.
5. Lampridou S, Bassett S, Cavallini M, Christopoulos G. The effectiveness of polynucleotides in esthetic medicine: a systematic review. J Cosmet Dermatol. 2025;24(2):e16721. PMID 39645667.
6. Araco A, Araco F. Preliminary prospective and randomized study of highly purified polynucleotide vs placebo in treatment of moderate to severe acne scars. Aesthet Surg J. 2021;41(7):NP866-NP874. PMID 33755110.
7. Rho NK, Chilukuri S, Chan G, et al. Expert perspectives: evidence-based applications of polynucleotides (PNs) in aesthetic medicine and dermatology. Clin Cosmet Investig Dermatol. 2026;19:557226.
8. Bos JD, Meinardi MM. The 500 Dalton rule for the skin penetration of chemical compounds and drugs. Exp Dermatol. 2000;9(3):165-169. PMID 10839713.

Common questions

Your questions,
answered