Rejuran, Juvelook, Exosomes

Hello, I am Dr. Dong Won Kim, Medical Director of Zero Lab Clinic, one minute from Hongdae (Hongik Univ.) Station Exit 1.

We are in an age of skin boosters flooding the market. There are so many products that even we get confused now and then. Rejuran, Juvelook, exosomes and so on — you have probably heard the names, but I imagine it is hard to tell how they actually differ. For a start the ingredients differ, and more than that, the very way they enter the skin is different. Coming to a consultation without knowing that can leave you with the wrong expectations. Today I want to lay out the three by ingredient, route of administration, bumps, and pain.

Rejuran, Juvelook, and exosomes differ from the ingredient up

Zero Lab Clinic has been selected as a Rejuran Diamond Member for two consecutive years, 2025 and 2026, and we have handled Rejuran-related procedures steadily. Drawing on that experience, let me start with how Rejuran, Juvelook, and exosomes differ. For reference, in a survey of 235 dermatologists in Korea, 88% said they perform polynucleotide injections, and three sessions at four-week intervals was reported as the most commonly recommended schedule[1]. What to do when something palpable appears after an injection is covered in What you feel after filler is usually just a lump.

2025 and 2026 Rejuran Diamond Membership

The most important column in that table is the middle one. Rejuran and Juvelook are procedures that place material inside the skin with a needle. Exosomes are not.

Exosomes are not something you receive by injection

Let me be clear about this, and give the conclusion first. There is no exosome product approved for injection in Korea. Nor is this a purely domestic situation. A review covering exosomes in aesthetics states that there is as yet no approved exosome-based product and that the clinical evidence remains at an anecdotal level[2]. A review from the regenerative medicine side likewise notes that the stem-cell-derived vesicle products on the market are distributed for topical use, and that standardization and regulatory questions remain unresolved[3].

For a procedure that puts something into the body by an unapproved route, there is no way to verify safety. It is also difficult to trace the cause if something goes wrong. A study analyzing complications of non-surgical aesthetic procedures at scale identified procedures with unsettled regulation as an area of growing risk, and gave exosomes as an example[4]. So we do not do it.

That said, not being able to use it as an injection does not at all mean it has no effect. Within the range where it is used topically, we do see a response that is not bad, and particularly so on skin where inflammation has flared up, as with acne. Exosomes are known to act on the anti-inflammatory side: in an experimental study using cells and an animal model in which inflammation was induced with acne bacteria, inflammatory mediators such as TNF-α and IL-6 decreased, and in the animals the degree was comparable to applying topical adapalene[8].

The evidence in people is still small. There is a case report of 3 patients with active acne in whom exosomes were applied after microneedling, where acne severity, pigmentation, and depressed scars had all improved at two months[9], and in an observational study comparing the left and right sides of the face in 9 adults, the side where exosomes were added to microneedling and CO2 laser did better on texture, hydration, firmness, and pigmentation[10]. These are case reports and a small observational study, so it is too early to speak with certainty, and even so, material like this is why we raise with you whether to add exosomes to a laser or microneedling procedure.

In short, exosomes are not "a skin booster you can choose instead of an injection." They are closer to care added on top of a procedure such as a laser. Which means it is hard to put them on the same line for comparison at all.

Bumps — how long do they last

Bumps are a reaction that arises with procedures injected by needle. So of Rejuran, Juvelook, and exosomes, this discussion applies to the first two.

• Polynucleotide preparations tend to produce bumps fairly often. In a split-face trial conducted by Korean investigators, bumps were observed in 56.7% with the existing formulation, and this fell to 13.3% with a formulation adjusted for pH and ion concentration[5]
• Collagen-stimulating products can form nodules if they bunch in one spot. Among 55 reported complications of collagen biostimulators in Brazil, nodules were the most common at 89.1%, and most appeared late, more than a month after the procedure[6]. So we do not inject shallow and concentrated enough to leave visible bumps; we spread it thinly across layers. A large volume pooling in one spot is the situation most to be avoided
• Exosomes are applied rather than injected, so the concept of bumps does not apply

You sometimes see Juvelook bumps explained along the lines of "they go down in a few days," and that too is a slightly risky thing to say. Injecting so that bumps show prominently is itself, in our view, a method that raises nodule risk. For reference, the complication report above pooled PLLA, CaHA, and PCL products rather than PDLLA, and the authors attributed the problem to product characteristics rather than to incorrect injection depth[6]. A systematic review pooling collagen-stimulating products likewise reported erythema, bruising, and nodules in 15~30%[7].

We look at the reconstitution process as much as the injection technique. Products in this family come as a powder, so before the procedure they go through a step of being reconstituted in water, and that step has long been one axis of safety management. For PLLA products in the same family, the manufacturer recommended reconstitution 72 hours before treatment for many years, and immediate reconstitution was permitted only in 2021. In a multicenter retrospective study of 274 treatments performed with immediate reconstitution, there was 1 nodule[11]. That means it is an area that stays under control when reconstitution is done properly, and by the same token that reconstitution is a variable. We keep to the guidelines on reconstitution time and concentration.

For Juvelook injections we mainly use an injector. When it is placed by hand, the amount that goes in at once and the depth rest on the practitioner's fingertips, whereas an injector device lets us keep that consistent. For preventing a large volume from pooling in one spot, we consider this the better option.

That said, this is a general standard, and there is individual variation by skin condition, treatment area, and injection volume. So as a rule we give a specific expected recovery period at the consultation.

Pain, and how it can be reduced

Rejuran and Juvelook use a needle, so some degree of pain is to be expected. Exosome application follows the pain of whatever laser or microneedling procedure it accompanies.

1) We apply topical anesthetic cream for a sufficient length of time before the procedure

2) Manage swelling and pain together with a cold compress right after

3) Do not force the interval between sessions shorter; keep to the recovery time

Especially if this is your first treatment, you may react more sharply to pain, so we explain the anesthesia method and the expected level of pain in advance at the consultation stage.

So which one is right for me

When weighing Rejuran, Juvelook, and exosomes, we suggest thinking along these lines.

• If dryness and skin texture are your concern, many people look at Rejuran first
• If firmness is your concern, many people consider Juvelook alongside it
• Exosomes are not a standalone choice; treat it as a question of whether to add it to a laser procedure you are already having

Of course no single one is the answer, and some people combine two. The accurate call comes from looking at the skin directly, so we go over it in consultation.

Attending the 2026 Rejuran Diameter Forum

This is not a matter of picking one of the three; you need to look at what your skin needs right now. Many people ask me which material is better, and my answer is always the same. Each has its own strengths, and what matters is what you need. Dryness, or firmness, or what to add to a laser — that order is enough.

Scars and pores are worked at yet another layer, so we covered each separately.

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References

[1] Rho NK, Han KH, Cho M, Kim HS. 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: https://doi.org/10.1111/jocd.16125

[2] Ku YC, Omer Sulaiman H, Anderson SR, Abtahi AR. The Potential Role of Exosomes in Aesthetic Plastic Surgery: A Review of Current Literature. Plast Reconstr Surg Glob Open. 2023;11(6):e5051. DOI: https://doi.org/10.1097/GOX.0000000000005051

[3] Davies OG, Williams S, Goldie K. The therapeutic and commercial landscape of stem cell vesicles in regenerative dermatology. J Control Release. 2023;353:1096-1106. DOI: https://doi.org/10.1016/j.jconrel.2022.12.025

[4] Rahman E, Rao P, Sayed K, et al. Decades of Scientific Data and Global Media Reporting on Complications in Non-surgical Aesthetic Treatments for a Transparent Safety Profile. Aesthetic Plast Surg. 2025;49(19):5567-5603. DOI: https://doi.org/10.1007/s00266-025-05007-3

[5] Jeon W, Park M, Kim SW, Kim J. Efficacy of Ionization-Adjusted PN Filler in Minimizing Injection Pain: A Randomized, Patient-Blinded, Split-Face Study. Aesthetic Plast Surg. 2025;50(7):2723-2730. DOI: https://doi.org/10.1007/s00266-025-05320-x

[6] Ianhez M, de Goes e Silva Freire G, Sigrist RMS, et al. Complications of collagen biostimulators in Brazil: Description of products, treatments, and evolution of 55 cases. J Cosmet Dermatol. 2024;23(9):2829-2835. DOI: https://doi.org/10.1111/jocd.16343

[7] Tam E, Choo JPS, Rao P, et al. A Systematic Review on the Effectiveness and Safety of Combining Biostimulators with Botulinum Toxin, Dermal Fillers, and Energy-Based Devices. Aesthetic Plast Surg. 2025;49(10):2809-2833. DOI: https://doi.org/10.1007/s00266-024-04627-5

[8] Li Y, Li S, Guo M, et al. Skin-Derived Precursors-Derived Exosomes Alleviated Acne Inflammation via TLR2/MyD88/NF-κB Signaling Pathway: In Vitro and In Vivo Studies. FASEB J. 2026;40(1):e71383. DOI: https://doi.org/10.1096/fj.202501944R

[9] Wan J, Yoon SE, Pamela R, et al. Lactobacillus-Derived Exosome Therapy for Active Acne Vulgaris, Post-Inflammatory Hyperpigmentation, and Atrophic Scarring. J Craniofac Surg. 2025. DOI: https://doi.org/10.1097/SCS.0000000000011408

[10] Vitale M, Ruri P, Marini S, Zappia E, Yi KH. Clinical Outcomes of Exosome-Augmented Microneedling and Laser Therapies in Full-Face Skin Rejuvenation: A Split-Face Observational Study. J Craniofac Surg. 2025. DOI: https://doi.org/10.1097/SCS.0000000000011807

[11] Vasconcelos-Berg R, Real J, Wenz F, Avelar LET. Safety of the Immediate Reconstitution of Poly-l-Lactic Acid for Facial and Body Treatment-A Multicenter Retrospective Study. J Cosmet Dermatol. 2024;23(12):3918-3923. DOI: https://doi.org/10.1111/jocd.16560

The references above are papers indexed in PubMed. This article provides general medical information; decisions about an individual's condition are made through consultation.