What Rejuran I is and how polynucleotides work under the eyes
Polynucleotides are chains of DNA fragments purified from salmon. Once injected into the dermis, they are proposed to form a water-binding, scaffold-like matrix and to stimulate fibroblasts, the cells that produce collagen. The retained water and new collagen are thought to thicken the lid skin, which makes the underlying vessels less visible. Because Rejuran I adds no meaningful volume, its effect is confined to skin quality, namely thickness, elasticity, hydration and fine lines.
- Injection Small droplets are placed into the dermis along the lower lid with a fine needle or an automatic injector. In a survey of 235 Korean dermatologists, most respondents used a 33G (very fine) needle with serial punctures into the dermis.
- Singapore registration Rejuran is listed on the Health Sciences Authority (HSA) Medical Device Register (DE0500702) for the face, with crow’s feet and the cheek named as treatment areas. The lower lid is not named, so under-eye use rests on the injector’s clinical judgement.
- Other names Clinics list it as Rejuran i, Rejuran Eye, PN eye booster or Korean PN Eyes. Polydeoxyribonucleotide (PDRN) is a related salmon-DNA ingredient made of shorter DNA fragments, and some price lists use the two names interchangeably.
Rejuran I suitability for thin skin, bluish dark circles and crepey lower lids
| Concern | What Rejuran I does | Evidence | Better-supported option if it does not suit |
|---|---|---|---|
| Blue-purple circles from thin skin | Thickens and hydrates the skin, making the veins less visible | C | Allergy control where the circles accompany rhinitis |
| Crepey lower-lid skin and fine lines | Improves texture, elasticity and hydration | C | Fractional CO2 laser for deeper crepiness |
| Brown, pigmented circles | Not designed to remove pigment | C (one uncontrolled study of another PN product) | Pico laser and lightening creams (Grade B) |
| A tear trough hollow | Adds almost no volume | D | Tear trough filler (Grade A for the hollow) |
| Fat-type eye bags | No effect on fat | D | Eye bag removal |
The stretch and light tests on the dark eye circles causes page distinguish thin skin and vessels from pigment and shadow.
Rejuran I results in published studies
- EvidenceEvidence for thin under-eye skin and fine lines, Grade C. In a randomised, double-blind split-face trial (27 patients enrolled), a polynucleotide product and a non-cross-linked hyaluronic acid booster produced similar overall improvement around the eyes after three sessions two weeks apart. The polynucleotide side showed greater improvement in roughness and pore volume and retained more of its gain in elasticity and hydration. A prospective study of 42 patients, without a control group, recorded improved lower-lid and crow’s-feet scores up to 3 months after treatment.
- EvidenceEvidence for periorbital darkness, Grade C. An open-label study of 61 patients treated with a different polynucleotide product recorded a shift towards milder periorbital pigmentation after three injections, with follow-up to 3 months. Because the study had no control group, the change cannot be attributed to the injections alone.
- EvidenceEvidence for a tear trough, Grade D. No controlled study has shown a reduction in tear trough depth with polynucleotides, and a 2026 review found no direct trials against hyaluronic acid filler.
- Studies of the Rejuran brand Most studies test polynucleotides in general rather than Rejuran I itself, so the grades above apply to the ingredient class. In a 2026 split-face trial of 25 women, Rejuran injected into the face after radiofrequency microneedling improved hydration, pore and wrinkle scores more than saline at 6 weeks. It produced no difference in dermal thickness or elasticity, the two measures most relevant to thin under-eye skin.
Rejuran I before and after timeline under the eyes
- Day 1 to 2 The small raised bumps along the lower lid settle as the injected product spreads into the tissue. A minority of patients bruise for up to a week.
- Weeks 2 to 8 The second and third sessions follow at intervals of 2 to 4 weeks.
- 3 months The published studies end at this point, with results measured after two or three sessions.
- 6 months Clinics advise a maintenance session at this point. No published study follows polynucleotides under the eyes beyond 3 months, so the interval rests on clinic practice rather than trial data.
Before-and-after photographs on clinic websites show selected cases, and differences in lighting and make-up alter the apparent darkness of the circles. The standardised photographs in the studies above provide a more reliable comparison.
Rejuran I price in Singapore (2026)
| Treatment | 2026 Singapore price | What the price covers |
|---|---|---|
| Rejuran I, one session | From S$500 (S$388 to 900) | Usually a 1 ml syringe, although some clinics price per 2 ml |
| Course of 3 sessions | S$1,200 to 2,700 | Package rates from about S$545 a syringe |
| Maintenance | S$388 to 900 a session | About every 6 months |
Prices are compiled from published Singapore clinic price lists, and some exclude GST. Some clinics list a generic “PN” or “PDRN” eye booster rather than the Rejuran brand, and a reliable quote names the product and the volume.
Rejuran I procedure, pain and downtime
- Preparation Make-up is removed, and numbing cream is applied.
- Treatment Multiple small injections are made along the lower lid, and each is felt as a sharp prick. No study has reported a pain score for Rejuran I under the eyes.
- Downtime Small bumps persist for 1 to 2 days, and bruising occurs occasionally.
- Sessions A course comprises three sessions 2 to 4 weeks apart, followed by maintenance about every 6 months. Three sessions four weeks apart was the protocol most often recommended in the Korean dermatologist survey.
Rejuran I side effects and risks
- Common Bumps at the injection points, redness, tenderness and bruising. No serious adverse events were reported in the randomised periocular trial.
- Fish allergy Because Rejuran is made from salmon DNA, a fish allergy should be disclosed to the doctor before treatment.
- Lumps and vessel blockage A 2026 expert panel article on Rejuran found no published case of granuloma (an inflammatory lump) or vascular occlusion (blockage of a blood vessel) from polynucleotides. In a rabbit study, polynucleotide injected into an artery caused only temporary flow disturbance, whereas cross-linked hyaluronic acid caused lasting blockage and tissue death. Animal results do not exclude the risk in people, and under-eye injection should be performed by a doctor.
- Infection Infection occurs rarely, as with any injection through the skin.
Rejuran I vs Juvelook, tear trough filler and pico laser
| Rejuran I | Juvelook | Tear trough filler | Pico laser | |
|---|---|---|---|---|
| Main effect | Thicker, better-hydrated skin, with no volume | Thicker skin plus slight volume | Fills the hollow immediately | Fragments brown pigment |
| Best for | Thin, bluish or crepey skin | Thin skin with a mild hollow | A shadow from a hollow | Brown pigment |
| Evidence, dark circles | C | C | B (A for the hollow) | B (pigment lasers) |
| Downtime | 1 to 2 days | 2 to 3 days | 1 to 3 days, with bruising up to a week | A few hours |
| 2026 Singapore price | From S$500 a session | S$388 to 688 a vial | S$600 to 1,200 a syringe (up to S$1,500) | S$250 to 800 a session |
Rejuran I and Juvelook share Grade C evidence, and the choice between them depends on volume, because Juvelook adds slight volume to a mild hollow whereas Rejuran I does not. Of the four options, only filler fills a definite hollow, and only pico laser removes pigment. The two boosters are compared in detail in Juvelook vs Rejuran, and Rejuran is compared with a hyaluronic acid booster in Profhilo vs Rejuran. Every option is compared by type on Dark eye circles treatment in Singapore.
Frequently asked questions about Rejuran under the eyes
How much does Rejuran I cost in Singapore?
Rejuran I costs from S$500 a session in Singapore in 2026, with a range of S$388 to 900. A course of three sessions costs S$1,200 to 2,700.
Does Rejuran I work for dark circles?
Rejuran I can thicken thin under-eye skin and make blue veins less visible, with Grade C evidence from small studies. It neither removes brown pigment nor fills a tear trough.
How many sessions of Rejuran I are needed?
The usual course is three sessions 2 to 4 weeks apart, followed by a maintenance session about every 6 months.
Is Rejuran made from salmon DNA?
Rejuran contains polynucleotides, which are DNA fragments purified from salmon. A fish allergy should therefore be disclosed to the doctor before treatment.
Is Rejuran or tear trough filler better for under-eye hollows?
Tear trough filler is usually the better option for a hollow, with Grade A evidence and correction of the groove in one session. Rejuran I improves the skin over a hollow but does not fill it.
General information, not medical advice. A registered medical practitioner should be consulted before any treatment. Dark Eye Circles Singapore does not sell treatments.
Sources and price references (checked 9 October 2026)
- 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. doi:10.1080/09546634.2020.1748857 (PMID 32248707) — Randomised split-face, 27 enrolled, PN vs non-cross-linked HA, 3 sessions 2 weeks apart; no serious adverse events https://doi.org/10.1080/09546634.2020.1748857
- Ziade G, et al. Prospective Observational Study of Polynucleotide Injections for Periorbital Rhytides. J Cosmet Dermatol. 2026;25(2):e70736. doi:10.1111/jocd.70736 (PMID 41689167) — Prospective observational, 42 patients, no control https://doi.org/10.1111/jocd.70736
- Amado R, et al. A Real-World Study of Polynucleotides HPT for Treating Periorbital Hyperpigmentation. Clin Cosmet Investig Dermatol. 2026;19:1–15. doi:10.2147/CCID.S605046 (PMID 42164086) — Open-label cohort, 61 subjects, 3 injections, 3-month follow-up; no control https://doi.org/10.2147/CCID.S605046
- Khan RS, Hafeez K. Hyaluronic Acid Fillers Versus Polynucleotides for Under-Eye Rejuvenation. J Clin Med. 2026;15(13):4971. doi:10.3390/jcm15134971 (PMID 42452433) — Literature review; no direct comparative RCTs https://doi.org/10.3390/jcm15134971
- Kim J. A Prospective Split-face Trial Evaluating Skin Recovery and Enhancement with Polynucleotide (Rejuran) Following Fractional Needle Radiofrequency Treatment. Plast Reconstr Surg Glob Open. 2026;14(9):e8109. doi:10.1097/GOX.0000000000008109 (PMID 42808113) — Split-face, 25 women, Rejuran 2 ml vs saline after fractional needle RF; 6 weeks; no difference in dermal thickness or elasticity https://doi.org/10.1097/GOX.0000000000008109
- Rho NK, et al. A survey on the cosmetic use of injectable polynucleotide: The pattern of practice among Korean Dermatologists. J Cosmet Dermatol. 2024;23(4):1243–1252. doi:10.1111/jocd.16125 (PMID 38093498) — Survey of 235 Korean dermatologists; infraorbital fine lines a top indication; 3 sessions 4 weeks apart most recommended https://doi.org/10.1111/jocd.16125
- Rho NK, et al. Expert Perspectives: Evidence-Based Applications of Polynucleotides (PNs) in Aesthetic Medicine and Dermatology. Clin Cosmet Investig Dermatol. 2026;19:557226. doi:10.2147/CCID.S557226 (PMID 41939258) — Expert panel on Rejuran; no reported granuloma or vascular occlusion with PN to date; evidence base limited https://doi.org/10.2147/CCID.S557226
- Boonpethkaew S, et al. Intravascular behavior of cutaneous polynucleotide injectables following intra-arterial exposure. Sci Rep. 2026. doi:10.1038/s41598-026-61442-5 (PMID 42457753) — Rabbit ear artery model; PN caused transient flow disturbance only; cross-linked HA caused persistent emboli and necrosis https://doi.org/10.1038/s41598-026-61442-5
- Health Sciences Authority, Singapore Medical Device Register: Rejuran, DE0500702 (data.gov.sg download, April 2026 listing) https://data.gov.sg/datasets/d_e697cc1e4caec596c0e9318fdd9420a3/view
- Rejuran I price: Sozo Aesthetic Clinic — Rejuran i from S$500 per session (checked 2026-10-05) https://sozoclinic.sg/dark-eye-circles/treatment/
- Rejuran I price: Halley Medical Aesthetics — S$490 (PDRN Skin Booster for Eye, 1 ml syringe) (checked 2026-10-05) https://www.halley.com.sg/price-list/
- Rejuran I price: SL Aesthetic Clinic — from S$480 (Korean PN Eyes) (checked 2026-10-05) https://slclinic.com.sg/price-list/
- Rejuran I price: Bay Aesthetics Clinic — S$388 first syringe; S$545 per syringe in a 3-syringe package (checked 2026-10-05) https://www.bayclinic.sg/treatment/rejuran-healer-skin-boosters/
- Rejuran I price: BA Clinic — S$650 per 2 ml (polynucleotide) (checked 2026-10-05) https://baclinic.sg/treatments/skinbooster/
- Rejuran I price: Dr Daniel Chang — S$400–800 (Rejuran PN / Juvelook) (checked 2026-10-05) https://drdanielchang.com/aesthetic-treatment-price-singapore/
- Rejuran I price: V Aesthetics Clinic (price list) — S$600 under-eye polynucleotide 1 ml (checked 2026-10-05) https://www.vaestheticsclinic.com.sg/price-list/
Dark Eye Circles in Singapore: this series
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