Rejuran injection in Korea on a short trip: what to watch once you're home

What does a Rejuran injection in Korea leave on your skin?

Small raised bumps where the product sits, some pinpoint redness and, now and then, a small bruise. The session runs about 10-20 minutes with numbing cream, and the clinic lists the downtime as short rather than none: you can walk out and get on the subway, but your face may not be ready for photos that evening.

What shows depends partly on how the product went in. The clinic describes three ways of delivering skin boosters, and each leaves a different trace:

Which method suits your skin and this product is decided in the consultation, by the same doctor who then does the treatment. Ask for the method name before you leave, because it changes what "normal" looks like in your mirror at home. If you're still unsure what the product is and why it isn't a filler, our explainer on Rejuran in Korea covers that ground.

The flight and the first two days back

The practical risks on a plane are touch, pressure and dry air, and all three are in your hands.

Cabin air is dry, and skin with fresh injection points can feel tight. A gentle, unscented moisturizer you already know is a better choice than a new sheet mask bought at the airport. Keep your hands off your face, and think about what will press on it for hours: a sleep mask resting on treated under-eye skin, a neck pillow pushing into your cheek, the window you lean against.

General advice after skin injections is to skip makeup until the injection points have closed, usually by the next day, and to avoid alcohol, saunas and hard workouts for the first day or two, since flushing can make swelling and bruising look worse. These are common precautions rather than fixed rules; the doctor treating you may adjust them to your skin.

Timing matters too. The clinic is open weekdays 10:00-19:00 and Saturdays 10:00-17:00, and closed on Sundays and Korean public holidays. If you fly out on a Sunday, Saturday is the last day you could be seen before leaving.

Which signs are normal at home, and which need a doctor?

Bumps, mild redness, small bruises and tenderness that fade day by day are expected. Redness that spreads, skin that turns hot, pus, fever, pain that grows after the second day, or a firm lump that gets bigger are not; see a doctor where you live the same day.

The literature backs the reassuring half. A 2024 systematic review of polynucleotides in esthetic medicine in the Journal of Cosmetic Dermatology found that reported side effects were mostly mild, short-lived injection-site reactions. For the warning half, the U.S. Food and Drug Administration's page on dermal fillers, a different product given by a similar needle-in-skin route, lists bruising, redness, swelling, pain, tenderness and itching as common effects, and infection and lumps among the less common ones.

The last row matters because polynucleotides used in skin boosters are typically derived from fish DNA, as a 2025 review in Pharmaceutics describes. Allergic reactions are not what the reviews mostly report, but anyone with a fish allergy should say so before the needle comes out, not after the flight home.

A one-page note for your dermatologist at home

A one-page note with the product name, the words "polynucleotide (PN) skin booster", the date, the delivery method, the treated areas, any numbing used, and your day-by-day photos. A doctor who has never handled the brand will still understand "polynucleotide injected into the dermis".

A few things make that note far more useful:

• Photos in the same light each day. The evening of the treatment, then the next morning and the morning after. Changes are easier to judge as a series than from one picture taken at the worst moment.
• Medicines and supplements. Anything that thins blood or makes bruising easier, plus any antibiotic or antihistamine you took after leaving Seoul.
• Allergies. Especially fish, and any reaction to earlier injections.
• What you did on the trip. A sauna on day one or a long night out changes how a doctor reads a bruise.

Interpreting is available in English, Japanese and Chinese.

Who should not have a Rejuran injection before flying home?

Anyone with an active skin infection, a cold sore outbreak or inflamed acne in the area should postpone, and so should anyone with a photo-critical event in the next two days. A few other situations call for a longer conversation before booking.

• Fish allergy or a past reaction to a PN product. Tell the doctor first; it may change the plan.
• Pregnancy or breastfeeding. Data on skin boosters in pregnancy are limited, and postponing is the usual choice.
• Blood thinners or easy bruising. Bruises are more likely and slower to fade. Don't stop a blood-thinning medicine on your own; ask the doctor who manages it.
• Wanting volume rather than skin quality. Rejuran does not fill a hollow. If volume is the goal, the Juvelook and Juvelook Volume comparison explains that different route.
• Textured acne scarring. A booster alone may not be the main tool; how a doctor reads acne scars covers the alternatives.

Individual skin varies, and suitability is confirmed only at the in-person exam.

How do you plan more than one session from abroad?

Most published polynucleotide protocols use a series of sessions a few weeks apart rather than a single treatment. When you live abroad, that leaves three realistic paths: one session per trip, timing trips to match the interval, or continuing the series with a doctor at home using the note from the section above.

There is no wrong choice among them; they differ in convenience, not in what the product does.

A few clinic facts help with the planning. Appointments are 1:1, one patient at a time in a private room, and the doctor who consults is the doctor who treats.

The clinic is at 2F, 165 Dosan-daero, Gangnam-gu (Sinsa Hill Building), about a 10-minute walk from Exit 8 of Sinsa Station on Line 3. The visit page has the map, and the clinic's English site lists who you may meet. If you're also thinking about a lifting device on the same trip, the Ultherapy FAQ covers its side effects so you can judge whether the trip has room for both recoveries.

If you're weighing a Korean Rejuran injection for your next trip, send two things on WhatsApp: a daylight photo of the area you want treated and the dates you'll be in Seoul.