Skin Booster, Rejuran, or Exosomes for Glass Skin?

TL;DR: Hyaluronic acid skin boosters fill the upper dermis with water and give a fast, visible glow. Polynucleotide injections (the Rejuran category) work more slowly, rebuilding the dermis itself over several weeks rather than just hydrating it. Exosomes have no approved medicine product in Korea yet, so we use them only as a topical add-on after a procedure that has already opened micro-channels in the skin, never as a standalone injectable. Which one comes first depends on whether a patient wants immediate shine or a longer-term change in texture.

A hyaluronic acid booster hydrates the skin fast, a polynucleotide injection rebuilds the dermis slowly, and an exosome add-on stays a recovery accessory rather than a standalone treatment, because Korea has not approved an exosome medicine yet. When a patient tells us they want "glass skin," we ask what that means to them before matching it to one of the three. Some people mean the wet, luminous look right after a good skincare routine. Others mean pores and fine texture that look smooth even in bare-faced daylight. Those are different targets, and the tools we get asked about most, hyaluronic acid (HA) boosters, polynucleotide injections, and exosome add-ons, address them on different timelines.

What each one is actually doing under the skin

An HA skin booster is a series of small injections of low-crosslinked hyaluronic acid placed across the upper dermis in many shallow points rather than one deep deposit. The HA binds water in place, so the skin looks plumper and more reflective almost immediately. A 2024 pilot study published in the Journal of Cosmetic Dermatology followed 20 patients between 30 and 60 years old through three micro-injection sessions spaced two weeks apart and reported that wrinkle scores had dropped by an average of 40 percent by the eight-week mark.

Polynucleotide, the ingredient behind the Rejuran category, comes from purified salmon DNA. Instead of adding water, it stimulates fibroblasts, the cells that produce collagen and elastin, so the change happens inside the dermis rather than sitting on top of it. A 2025 review published in Applied Sciences compiled results from a randomized split-face trial that injected HA on one side of the face and polynucleotide on the other. The polynucleotide side scored higher on aesthetic improvement at 16 weeks and showed a larger drop in skin roughness at 28 weeks. Both of those measurement points come later than the HA booster's eight-week result above, and the review did not track outcomes beyond 28 weeks, so we cannot say from that data whether the gap holds at six months or a year.

Exosomes are the newest name in this group, and the regulatory picture explains why we treat them differently from the other two. A 2026 regulatory and safety review published in Dermatological Reviews noted that Korea's Ministry of Food and Drug Safety classifies exosomes as biologics and issued manufacturing and testing guidelines for them back in 2018, yet no exosome-based medicine has received formal approval in the country. A 2026 systematic review published in the Journal of Cosmetic Dermatology looked at eight studies of microneedling combined with exosomes and found early signals for skin texture and tone that were consistently positive, but every study in the review had a small sample and none followed patients past six months.

That gap between "promising early signal" and "approved medicine with a known dose" is exactly why we do not offer exosomes as a standalone injection. We use them only as a topical solution applied right after a procedure that already leaves micro-channels open in the skin, as a recovery-phase add-on rather than a treatment in its own right.

Choosing based on the days you actually have

The clinical trials behind both HA boosters and polynucleotide injections were built around a three-session series spaced two weeks apart, not a single visit. The exosome review found so much variation in product source and application protocol across studies that it could not point to a standard number of sessions at all. Practically, this means neither a full HA series nor a full polynucleotide series finishes inside one short trip. During the consultation we look at the diagnosis first, then decide together what fits into this visit and what gets scheduled for a return trip.

Timing inside the trip matters just as much as the choice between ingredients. Injection series leave temporary micro-channels at each entry point, and we do not recommend makeup on the same day. If a flight home is the next morning, we build in a buffer day rather than scheduling an injection session on the last evening. We keep a fuller breakdown of recovery windows by procedure type in our guide to makeup timing after a skin procedure, which is worth reading alongside this one if the schedule is tight.

Our Gangnam location sits inside the UH FLAT SIGNATURE Gangnam building, and guests staying at the hotel have access to an oxygen chamber and a vitamin IV drip at no extra charge. That means a patient can go from the treatment room straight up to a room and let swelling and redness settle without another commute. English, Japanese, and Chinese interpreters are on staff, so questions about what is actually going into the skin do not get lost in translation during the consultation.

FAQ

Can all three be done on the same visit?

Hydration and dermal remodeling target different layers, so we do sometimes plan HA and polynucleotide sessions in the same stay. Stacking a large injected volume in one sitting extends swelling and bruising, though, so for a short trip we usually spread sessions across separate days rather than compressing them into one.

Will one session be enough to notice a difference?

Many patients see a visible change in glow after the first HA micro-injection session. Polynucleotide is different: the trial data behind it was built on a three-session series, so judging the result after a single session does not reflect what the treatment is designed to do.

If I have a fish allergy, should I avoid polynucleotide?

A 2026 review published in the Journal of Cutaneous and Aesthetic Surgery recommends a patch test before treatment for anyone with a history of fish hypersensitivity, since the ingredient is purified from salmon DNA. Tell us about any allergy history during the consultation and we will check it before the diagnosis stage moves any further.

The right combination for glass skin comes down to skin condition and the calendar, not a fixed package. We look at both during the diagnosis before narrowing the options down.