Medically reviewed by Dr Sin Yong · Last reviewed · 13 min read · Doctor-performed, never delegated · Jump to questions
Rejuran Singapore in brief: Rejuran is an HSA-registered polynucleotide injection, derived from salmon DNA, that a doctor places in the skin to support repair and skin quality. It is a medical treatment, which is different from the Rejuran-branded creams and ampoules sold in shops. In Chinese it is sometimes called 婴儿针.
Related: Profhilo vs Rejuran.
Dr Sin Yong · MBBS (NUS) · MRCS (Edin) · MSc Aesthetic Medicine with Distinction (Queen Mary, London) · MSc Practical Dermatology (Cardiff) · Global Key Opinion Leader
A polynucleotide preparation purified from salmon DNA, delivered by intradermal micro-injection. It is directed at how the skin repairs itself: not at volume, not at lift, not at pigment.
Rejuran Healer is a polynucleotide skin booster purified from salmon DNA and registered with Singapore's Health Sciences Authority as an injectable medical device. It is injected into the dermis to support skin repair, texture and elasticity. It is not a filler: it adds no volume, does not lift and does not remove pigment. Fish allergy is checked first.
Also called: polynucleotide (PN) injections, 婴儿针, リジュラン
Rejuran is made by PharmaResearch in Korea and is registered with Singapore's Health Sciences Authority as an injectable medical device, administered by a doctor. The active material is polynucleotide: chains of nucleotides purified from salmon DNA, filtered and sterilised so that what is injected is the polymer, not genetic information. The standard facial preparation carries polynucleotide at approximately 20 mg/mL, around 2 per cent, in chains across a molecular weight range of roughly 50 to 1,500 kDa.
“Nobody is injecting fish into your face. Here is what is actually in the syringe. Purified DNA fragments.”
Dr Sin YongOn what polynucleotides are
Two terms get used interchangeably and should not be. PN denotes polynucleotide, the longer-chain material in this range. PDRN denotes polydeoxyribonucleotide, shorter fragments of the same family used in other preparations. Products built on each are not the same product.
Polynucleotides act on the repair environment of the dermis rather than on its bulk. Two effects are described in the literature: an influence on fibroblast activity and extracellular matrix turnover, and signalling through adenosine A2A receptor pathways, which is also the route of the molecule's described anti-inflammatory action. The material also behaves as a hydrophilic polymer in the tissue. The practical consequence is that it is directed at how skin behaves rather than at how much of it there is: it changes no dimension of the face, and tissue that is signalled to repair still has to do the repairing.
“Rejuran signals the skin to repair. It does not fill, it does not lift, and it does not remove pigment.”
Dr Sin YongOn what polynucleotides do
A Rejuran facial usually means Rejuran Healer injections, not a facial in the spa sense. The name has stuck because the treatment covers the whole face, but the product works only because it is placed into the dermis by micro-injection, which in Singapore is a medical treatment performed by a doctor. Some salons apply polynucleotide or salmon DNA serums to the surface, sometimes after a device that creates fine channels. A topical serum does not deliver the same material to the same depth, and findings from studies of the injectable cannot be transferred to it.
Where a booster has been placed alongside filler and a lump has formed, see lumps after filler and skin boosters.
Bumps, swelling and other side effects after a booster: see skin booster side effects.
The treatment is directed at skin texture, fine lines, elasticity and the quality of post-acne skin: dermal-quality complaints, where a repair signal is a sensible thing to deliver. Examination looks at the skin under good light and under stretch, because post-acne skin has to be sorted into rolling scars, boxcar scars, ice-pick tracts and residual redness or pigment that is not scarring at all.
| Group | Typical situation | What usually happens |
|---|---|---|
| Tends to suit | Texture and fine-line concerns; reduced elasticity or tired-looking skin quality; post-acne skin quality as one part of a wider plan | Preparation chosen for the area after assessment |
| Not suitable, or assessed carefully | Fish or salmon allergy, because the material is purified from salmon DNA | Assessed directly; a different skin booster may be chosen |
| Better to wait | Pregnancy or breastfeeding; active infection or inflamed skin at the injection site | Treatment deferred |
| Caution | Keloid tendency where injecting in or around scars; blood-thinning medicines or a bleeding tendency; allergy to topical anaesthetic | Weighed and discussed before injections are planned |
| Different plan needed | Volume loss or hollowing; melasma or pigmentation; tethered or fixed-wall scars | A structural, light-based or scar plan instead of, or alongside, the injectable |
Men are assessed the same way, and thicker, oilier skin with acne scarring is examined under stretch. Anyone expecting volume, a lift, pigment clearance or smaller pores is being offered the wrong treatment. Fish allergy, who should wait and which preparation fits are covered in more detail under am I suitable for polynucleotide injections.
The range has four preparations, formulated differently and not interchangeable. Which is appropriate is decided at examination, not by product choice.
| Preparation | What it does | What it cannot do | Who it tends to suit |
|---|---|---|---|
| Healer | Standard facial preparation: polynucleotide at about 20 mg/mL placed intradermally across the face | Add volume, lift or clear pigment | Texture, fine lines, elasticity and overall skin quality on the face |
| S | Higher-viscosity preparation placed into and around scars | Release a tethered scar or resurface a fixed-wall scar | The skin-quality component of acne scarring, alongside structural scar work |
| I | Lower-viscosity preparation for the thin periorbital skin | Correct hollowing, shadow or herniated fat under the eyes | Fine lines and crepey skin around the eyes, once the under-eye cause is diagnosed |
| HB | Polynucleotide combined with hyaluronic acid in one syringe | Replace a filler or a structural treatment | Skin that needs both a repair signal and hydration |
The whole-face preparation has its own page, the whole-face preparation explained, and the periorbital one is covered under the under-eye preparation, including how it differs from tear trough filler. Scar use is set out under polynucleotides for acne scars.
It adds no volume and does not lift; it is a polynucleotide directed at how skin behaves, not how much of it there is.
A pore is a fixed opening and pigment is a chromophore problem; the injections address texture and dermal support only.
Like any injectable, it carries risks that should be stated before treatment. The common effects are local and expected: small papules at the injection points, swelling, tenderness and bruising, more so around the eyes where skin is thin and vessels superficial. Less common are nodules where material sits unevenly or too superficially, and infection. Allergic reaction is rare, which is why fish allergy is asked about directly rather than assumed absent.
Safety also depends on who is treated and where. It is not used in pregnancy or while breastfeeding, or through active infection or inflamed skin, and a keloid tendency is weighed before injecting near scars. It is given with sterile technique by a doctor; a product of uncertain origin, or injection outside a medical setting, removes the safeguards that make the treatment predictable. Registration is a safety baseline, not a promise of result.
Small bumps at each injection point are expected after Rejuran, and on their own they are not a sign that anything has gone wrong. Polynucleotides tend to leave more visible bumps at first than a hyaluronic acid booster, and the bumps flatten as the swelling settles and the polynucleotide is taken up.
A bump that is still there once the rest of the skin has settled is different: it is scanned before anything is decided. Ultrasound shows where the product sits, how deep it is and how far it has spread, and what it is likely made of. It also shows whether filler or another booster placed earlier sits in the same area. The scan does not prove what a bump is; where it does not look like product, further tests are arranged. How a lasting bump is treated without surgery is set out in lumps after skin boosters.
A bump that is red, hot, painful or swollen, or a fever, needs a doctor the same day; if no doctor can see you today, go to A&E. It is treated medically first. Pale, dusky or mottled skin, or pain that is getting worse, needs urgent assessment by the doctor who injected you, or at A&E, now; a change in vision or eye pain: call 995 now. More is in skin booster side effects.
Topical anaesthetic is usual. Delivery is by fine needle in a distributed pattern of micro-injections, or by an injector device placing small volumes at a set depth; which is used depends on the area. Most people describe a series of small pricks with some stinging, and the skin around the eyes and over scars tends to be more sensitive. Small papules or wheals appear at the injection points as the material sits. That is the expected appearance, not a complication.
The sequence below describes phases, not a timetable: how quickly each passes depends on the area and the person, and is discussed at consultation.
The papule pattern, the make-up rules and what is not normal are described in full under downtime after polynucleotide injections, and the cleansing and sunscreen rules on the aftercare page.
Treatment is planned individually, so cost follows the plan rather than a published list. It depends on the area treated, since full face differs from the periorbital area alone or from a defined field of scarred skin; which preparation the assessment indicates; the amount used and the delivery method; whether one modality or several are needed, since a structural scar needs structural work alongside; and how the plan is staged. A written quote is given at consultation, after Dr Sin Yong has assessed the skin, and the consultation decides whether the treatment is advised at all. What sets the fee, preparation by preparation, is on cost factors, and how quotes work is on how we quote.
Dr Sin Yong, an aesthetic physician, assesses the skin and performs the injections himself at his practice on Orchard Road. His first question is whether the problem is skin or structure. A skin-quality complaint may need only an injectable; a hollow, a descended contour or a tethered scar needs a structural plan, and he says so rather than offering a skin booster for a concern it cannot reach.
For post-acne skin he often pairs the injectable with resurfacing or RF microneedling, because a polynucleotide addresses skin quality while tethered or fixed-wall scars need subcision or resurfacing. It can also sit alongside pigment treatment, or a filler for a separate structural problem. The order and spacing are decided at assessment so each treatment is given at a sensible point in healing, and the preparation and any interval between visits are set individually at review rather than quoted in advance.
At a licensed medical clinic, because Rejuran Healer is registered with Singapore's Health Sciences Authority as an injectable medical device and is placed in the dermis by a doctor. Dr Sin Yong assesses the skin and performs the injections himself at his practice on Orchard Road, Singapore. Salon facials that apply polynucleotide or salmon DNA serums to the surface are a different treatment and do not deliver the same material to the same depth.
No. Nothing in the range is engineered to occupy space or hold a contour, and none of it corrects a structural deficit. Rejuran is directed at the repair environment of the dermis: fibroblast activity, matrix turnover and inflammatory signalling. A hollow or a deficient jawline needs material designed to stay where it is placed, which is a different class of product entirely.
Healer is the standard facial preparation. S is formulated at a higher viscosity for scarred skin, where material is placed into and around the scar rather than spread across a field. I is lower in viscosity and intended for the thin skin of the periorbital area. HB combines polynucleotide with hyaluronic acid. Which is appropriate is decided at examination.
Fish allergy is asked about directly before Rejuran is offered, because the polynucleotide is purified from salmon DNA. Allergic reaction is rare, but a fish or salmon allergy is a reason to assess carefully or choose a different skin booster. Tell the clinic about any fish or seafood allergy at consultation, along with pregnancy, active skin infection and any keloid tendency.
Post-acne skin contains several different things: rolling scars tethered to the dermis, boxcar scars with a fixed wall, ice-pick tracts, and residual redness or pigment that is not scarring at all. A polynucleotide addresses the skin-quality component. A tethered or fixed-wall scar is a structural problem and needs structural work, subcision or resurfacing, alongside it.
Topical anaesthetic is usually applied first, and most people describe a series of small pricks with some stinging as the material is placed. The skin around the eyes and over scars tends to be more sensitive. Comfort is checked during treatment, and delivery by fine needle or injector device is chosen according to the area.
Not straight away. Small papules sit at each injection point at first, and make-up, heat, alcohol and vigorous exercise are avoided while they begin to flatten. When to restart make-up is given in the aftercare instructions, because it depends on how the skin settles and whether bruising appeared. Increasing pain needs urgent assessment by the doctor who injected you, or at A&E, now. Spreading redness or swelling that does not subside needs a doctor the same day (A&E if no doctor can see you today) rather than being covered up.
The fee depends on the area treated, which preparation suits the skin, the amount used, the delivery method and whether it is combined with another treatment. A written quote is given at consultation, after Dr Sin Yong has examined the skin. No price is set beforehand, and the consultation decides whether the treatment is advised at all.
No. The creams, ampoules, masks and sunscreen sold in shops under the Rejuran name are cosmetics applied to the skin surface. The Rejuran treatment is an injectable medical device placed in the dermis by a doctor. Skincare can support the skin barrier, but a product on the surface is not placed in the dermis, so the two should not be expected to do the same thing.
It is used across skin types and in Asian skin, and it does not carry the pigment risk of some heat-based treatments. It is avoided with a fish or salmon allergy, during pregnancy and breastfeeding, and with active infection or inflammation at the site. Suitability is decided at examination.
No. Treatment for appearance is not claimable under MediSave or MediShield Life, and most private insurance plans exclude it. If you have a question about your own policy, check with your insurer before booking.
In Singapore, 婴儿针 (literally “baby injection”) is a nickname often used for polynucleotide skin boosters such as Rejuran. The name is used loosely for different products, so ask which product is meant; the nickname does not describe a result.
Available on Orchard Road, Singapore. By appointment with Dr Sin Yong. WhatsApp enquiries are answered in English and Chinese.
Medically reviewed by Dr Sin Yong, MBBS (NUS), MRCS (Edinburgh) · Last updated 23 October 2026 · Editorial policy
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