DOCTOR'S COLUMN

Clinical notes written personally by Dr. Park Hyungkwon — covering treatment principles, aftercare, and the director's perspective.

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Philosophy2026.04.29

Before you book an appointment, read this

I am Dr. Park Hyungkwon, director of LUNN Clinic in Cheongdam. Here is why I chose a single-doctor practice, with one person responsible from consultation through treatment and aftercare, and what I hope you will check before booking.

Botulinum toxin2026.09.23

Skin Botox: Do you really need it every three months?

Does skin Botox really wear off every three months? The clinic director explains how the noticeable duration varies with skin condition and treatment goals, and how to decide on repeat treatment. Effects are generally reported to last 8–12 weeks, but this is…

Skin boosters2026.09.23

Under-eye wrinkles and dark circles: can Rejuran I help?

A dermatologist explains how Rejuran I acts on under-eye wrinkles and dark circles, and the supporting evidence. Learn about the timing of effects, the procedure, and side effects. Injecting salmon-derived ingredients into the dermis around the eyes aims to help skin recover itself rather than simply fill wrinkles.

Body & other treatments2026.09.23

Fat-dissolving injections: an honest look at Newbizu swelling and recovery

If you are considering Newbizu fat-dissolving injections, swelling and recovery are likely key concerns. This candid comparison draws on clinical experience. Fat-dissolving injections reduce volume by breaking down fat cells; Newbizu is one example.

Acne, scars & pores2026.09.23

Inflammatory acne: Gold PTT treatment frequency and intervals for reducing recurrence

When considering Gold PTT for pustular acne, session planning and intervals influence recurrence. We explain the mechanism, side effects, and suitable candidates from a clinical perspective. Pustular acne involves deep, recurring sebaceous inflammation; Gold PTT deposits gold microparticles in follicles and sebaceous glands, then applies near-infrared laser energy.

Botulinum toxin2026.09.23

Calf Botox: when to treat muscular calves

Calf Botox is a treatment for muscular calves. Our dermatologist explains suitable candidates, the timing of effects, and precautions. It is used when developed muscles make the calves prominent; the same effects are difficult to expect when fat or swelling is the cause.

Skin boosters2026.09.23

Rejuran in Cheongdam: how many days do swelling and bruising really last?

A dermatologist explains how long swelling, bruising, and raised bumps can last after Rejuran in Cheongdam, and when they may persist longer. Swelling and bruising are usually managed as temporary reactions that settle within 1 week.

Lifting & firmness2026.09.23

Ultherapy and Thermage together: do their effects overlap?

Do Ultherapy and Thermage duplicate each other's effects? This column explains their target layers, mechanisms and sequencing. Ultherapy focuses ultrasound into points in the dermis and SMAS, a deeper tissue layer, to stimulate collagen regeneration.

Pigmentation & redness2026.09.23

Laser toning near Gangnam Station: why one session may not clear pigmented spots

Why does laser toning at a Gangnam Station dermatology clinic require repeated sessions? A dermatologist explains the mechanism, differences between spots and melasma, session-by-session changes and adverse effects. Q-switched laser toning breaks melanin into small particles.

Lifting & firmness2026.09.23

Sofwave: how it works, results and how long they last

A dermatologist reviews the mechanism, effects and duration of Sofwave using published evidence, addressing questions before treatment. Sofwave delivers ultrasound uniformly to the mid-dermis in parallel beams rather than focusing it at one point.

Lifting & firmness2026.09.23

Ultherapy in Gangnam: why does the shot count vary between clinics?

Why do clinics offer different shot counts and energy levels for Ultherapy in Gangnam? This article explains how depth, treatment area, and clinician skill affect results. Searching for Ultherapy in Gangnam quickly reveals that advertised shot counts differ by clinic.

Lifting & firmness2026.09.23

Eye Thermage for fine lines: how does it differ from Thermage?

A dermatologist explains how Eye Thermage differs from standard Thermage, how the eye-area tip works, and who may benefit. Learn about discomfort, recovery, and treatment selection. Eye Thermage uses a small radiofrequency tip designed for precise treatment of fine lines around and under the eyes.

Skin boosters2026.09.23

Skin boosters compared: Rejuran, Juvelook or Rituo?

Skin boosters include hyaluronic acid, PN, collagen-stimulating, and hADM categories with different purposes and response speeds. The medical director explains Rejuran, Juvelook, and Re2O, and how to choose among hydration, regeneration, and tissue-support approaches.

$Pore reduction: How to choose Potenza, pico-fractional laser, or skin Botox$

Botulinum toxin2026.09.23

Pore reduction: How to choose Potenza, pico-fractional laser, or skin Botox

A dermatologist explains how Potenza, pico-fractional laser, and skin Botox suit different pore concerns, including their mechanisms and selection criteria. These are three commonly compared options for improving the appearance of pores.

Skin boosters2026.09.23

Hydrating skin injections and SKINVIVE: what is the difference?

A comparison of water-glow injections and Skinvive, covering their ingredients and how their effects differ. A dermatologist explains selection criteria based on clinical experience. Water-glow injections are a common hydrating skin booster and are classified in the same broad category as Skinvive.

Fillers2026.09.23

Nasolabial folds: can Mihee injections replace fillers?

How do Mihee injections and fillers differ for nasolabial folds? We explain the difference between filling and stimulating collagen production, along with selection criteria. Mihee injections stimulate cells in the dermis to produce their own collagen rather than directly supplying collagen.

Lifting & firmness2026.09.23

ONDA lifting for a sagging double chin

A review of how ONDA lifting targets double-chin sagging, the clinical evidence, suitable candidates and precautions. ONDA is a noninvasive microwave treatment for both under-chin fat and laxity. Clinical reports describe significant improvement after 6 sessions…

Botulinum toxin2026.09.23

Skin Botox: can it really reduce the appearance of pores?

How true is the claim that skin Botox can reduce pores? We examine its mechanism and limitations, expected effects, and suitable candidates. Skin Botox distributes small amounts of Botox widely in the superficial skin to reduce sebum secretion and fine muscle movements.

Skin boosters2026.09.23

Radiesse and Sculptra: how do these collagen boosters differ?

Before considering Radiesse, understand how it differs from collagen boosters such as Sculptra. Here are their ingredients, mechanisms and suitable candidates. Radiesse is a calcium-based filler that provides immediate volume while also stimulating collagen production.

Skin boosters2026.09.23

Rituo: which skin types is it suited to, and how many sessions are needed?

Rituo is a skin booster using acellular dermal material. We explain its mechanism, suitable skin types, and recommended sessions and intervals. It injects human-derived acellular dermal matrix (hADM) processed into microparticles.

Lifting & firmness2026.09.23

Facial lifting: When should you start?

If you are considering facial lifting, first understand the early signs of sagging and when to consider treatment. This guide covers assessment and treatment selection. The early stage, when cheeks begin to sag and reduced firmness becomes noticeable, is often considered an appropriate time to consider facial lifting…

Fillers2026.09.23

Lip filler: Amount and design for a natural-looking result

This guide explains how filler amount, Cupid's bow design, and volume placement contribute to natural-looking lips, alongside swelling, duration, and product selection. Lip filler uses hyaluronic acid gel to enhance lip volume and contour.

Pigmentation & redness2026.09.23

Lasers for melasma and pigmented spots: how do they differ from toning?

Before a pigment-laser consultation, understand how melasma toning differs from treatment of discrete dark spots. A dermatologist explains their principles, energy settings, sessions and recovery. The same device can be used, but the settings and approach differ.

Acne, scars & pores2026.09.23

Potenza: why is it often recommended for pores and scars?

We explain why Potenza is recommended for pores and acne scars through dermal heating while preserving the epidermis, and how its role differs from fractional pico laser and skin Botox. Potenza delivers radiofrequency into the dermis through microneedles to encourage collagen regeneration while preserving the surface.

Botulinum toxin2026.09.23

Temporalis Botox: How does it differ from masseter Botox?

Temporalis Botox reduces the strength of the temple muscles. Its target and purpose differ from masseter Botox used to refine the jawline. This guide explains the differences and selection criteria. Temporalis Botox involves injecting Botox into the temporalis muscle to reduce excessive tension.

Skin boosters2026.09.23

AestheFill in Gangnam: Realistic expectations for collagen-booster duration

If you are considering AestheFill at a Gangnam dermatology clinic, you may wonder how long a collagen booster really lasts and when results become noticeable. This guide offers practical expectations based on clinical experience. AestheFill helps stimulate collagen production within the skin.

Acne, scars & pores2026.09.23

Acne scars: 3 things to check before CureJet treatment

If you are considering CureJet for acne scars, first check how it works, the strength of the evidence, possible side effects, and suitable scar types. Here are three criteria to know before consultation. Acne scars require very different approaches depending on the form of the scar tissue.

Pigmentation & redness2026.09.23

Pico toning: why does melasma pigmentation return?

Considering pico toning? A dermatologist explains why melasma can darken again, how to reduce recurrence, and the principles and precautions involved. Pico toning uses short pulses of laser energy to break melanin into smaller particles to improve melasma and other pigmented spots.

Acne, scars & pores2026.09.23

Small acne bumps: why extraction and anti-inflammatory injections may not be enough

We explain why closed comedones recur, how they form, the roles of extraction, anti-inflammatory injections, and Gold PTT, and care to reduce recurrence. Closed comedones develop when tiny openings in the skin become blocked with dead skin cells and oil.

Fillers2026.09.23

Forehead fillers in Gangnam: principles for a natural contour

A dermatologist explains forehead contours, filler volume and injection layers, swelling care, clinic selection, side effects, and recovery before considering forehead filler in Gangnam. Small divided amounts of hyaluronic acid are placed in a shallow layer over the forehead bone to soften the contour.

Pigmentation & redness2026.09.23

Facial redness: why do visible vessels worsen every summer?

Explore the causes of facial redness, why visible vessels worsen each summer, and how wavelength-based treatments work. Sessions, side effects, and recovery are also covered. Facial redness most often stems from dilated vessels making hemoglobin visible through the skin.

Botulinum toxin2026.09.23

Hyperhidrosis: how long does Botox last for sweaty palms and underarms?

For individuals considering Botox for excessive sweating (hyperhidrosis), a dermatologist has summarized the principles, effectiveness, and duration of the treatment, as well as the ideal candidates. They have also provided a list of things to check before undergoing the procedure. A common treatment for hyperhidrosis involves injecting Botox to temporarily block the nerve signals that stimulate sweat glands, thereby reducing sweat production.

Skin boosters2026.09.23

When do exosomes begin to show their regenerative effects?

A dermatologist reviews when exosome treatments may show regenerative effects, how they are combined with microneedling, how long results may last, and possible adverse effects. Exosomes are a booster treatment that delivers nanoscale signaling molecules secreted by cells, rather than the cells themselves, to the skin to promote regeneration and collagen synthesis.

Skin boosters2026.09.23

Why alternate Juvelook and Rejuran treatments?

Juvelook and Rejuran are skin boosters with different mechanisms. This column explains their differences and the potential benefits of alternating them. Juvelook stimulates new collagen formation; Rejuran provides regenerative signals that support damaged skin's own recovery…

Botulinum toxin2026.09.23

Masseter Botox: when do results appear and how long do they last?

When does masseter botulinum toxin take effect, and how long does it last? The doctor explains onset, duration and retreatment intervals. It softens the jawline by reducing chewing-muscle strength. Change usually begins around 2 weeks, with duration varying…

Skin boosters2026.09.23

Stem cell treatments for skin regeneration: 2 things to know beforehand

We explain how stem-cell procedures actually work and the regulatory situation in Korea, focusing on 2 key points to check beforehand. Their action involves skin regeneration driven by signaling substances secreted by cells, rather than primarily by the cells themselves.

Skin boosters2026.09.23

Can Sculptra improve volume and firmness together?

Sculptra stimulates collagen production to gradually improve volume and firmness. Dr. Park explains how it works, when changes may appear, and what to consider before treatment. Its poly-L-lactic acid (PLLA) stimulates cells within the skin to produce their own collagen.

Acne, scars & pores2026.09.23

Scar lasers: which treatment is right for me?

Scar laser treatment is selected according to scar type. This guide covers devices and recovery for depressed scars, red marks, and pigmentation. The suitable device depends on the scar's shape, color, and depth.

Fillers2026.09.23

Under-eye hollows: fillers or Rejuran I?

A dermatologist explains under-eye hollowing, how it differs from dark circles, and when filler or Rejuran I may be suitable, including swelling and duration. Under-eye hollowing is a shadow-producing depression that develops as fat beneath the eyes and cheek tissue become thinner.

Skin boosters2026.09.23

Rejuran: an honest guide to recovery and treatment sessions

An explanation of recovery and recommended sessions after Rejuran Healer, beginning with its mechanism. Redness, raised bumps, and cumulative effects are discussed with individual variation in mind. Rejuran is a regenerative procedure using salmon-derived ingredients to send recovery signals to skin cells.

Fillers2026.09.23

Fillers: is filling selected areas enough?

Before filler, assess overall facial balance rather than simply filling individual areas. This article explains hyaluronic acid filler and planning principles. Filler uses hyaluronic acid gel to restore volume and contour. Rather than placing a preset amount in a preset area, the face…

Philosophy2026.04.22

Choosing a thread-lifting clinic: advice after three disappointing treatments

If Ultherapy, Thermage or thread lifts have not made a difference, diagnosis and planning may matter more than the device. A Cheongdam dermatologist explains three criteria for choosing a lifting practice.

Fillers2026.04.15

More filler for nasolabial folds is better? Why a doctor may advise against it

When nasolabial filler still looks unnatural, direction rather than amount may be the issue. This article explains vector-based planning for midface volume loss and what to assess before treatment.

Pigmentation2026.04.08

No change after ten pico-toning sessions? A doctor explains possible reasons

Why can the same pico toning produce different results? Wavelength, energy, and treatment intervals matter. We explain protocol differences for people whose melasma remains despite repeated laser toning.

Acne2026.04.01

Adult acne at work: is Gold PTT the answer? 3 honest answers

Recurring chin acne in working adults calls for addressing the sebaceous glands themselves. This column explains how Gold PTT differs from conventional acne treatment and when it may be suitable.

Aftercare2026.03.25

Ice packs for Ultherapy pain? Why a doctor may not recommend them immediately

Cold packs may be the first thing you reach for to relieve pain and swelling after lifting treatment, but timing matters immediately after heat-induced regeneration. This article outlines aftercare following Ultherapy and Thermage.

Clinic2026.03.18

Why I opened a solo-doctor clinic despite everyone’s advice against it

I believe the doctor who consults should also perform the treatment. Here is why I run a single-doctor clinic in Cheongdam, and what changes when care is provided by a dermatologist.

Fillers2026.03.11

Under-eye fillers: ignoring the type of dark circle can make it look darker

Dark circles can be pigment-related, vascular or structural, and under-eye filler is an answer for only some of them. This column explains how we assess under-eye hollowing and the tear trough.

Philosophy2026.03.04

Why I leave the final 0.1 cc: finishing facial asymmetry treatment

Filler often looks obvious because of left–right balance rather than amount. This article explains how small amounts are used to refine symmetry, and why I leave the final 0.1 cc in reserve.

Lifting2026.02.25

Ultherapy or Thermage: what is different, and do you need both?

Ultherapy addresses the SMAS layer, while Thermage works on the dermis and fat layer. They have different roles rather than being substitutes. Here are their differences and the criteria for combining and sequencing them.

Lifting2026.02.18

Sofwave: 4 situations when a doctor may advise against it

Sofwave targets the shallow dermis and involves relatively less discomfort. Here is why it may be considered for people with thin skin or those who found other lifting treatments too painful.

Lifting2026.02.11

ONDA lifting intervals: is more frequent better? First distinguish fat from sagging

Treatment differs depending on whether a double chin comes from fat or sagging. This article explains when ONDA lifting may be suitable, treatment intervals, and how we assess jawline definition.

Lifting2026.02.04

Facial sagging: is it time to start lifting treatments? 4 signs

Earlier is not always better for lifting, and neither is delaying it. Here are 4 signs, including sagging cheeks and a less defined jawline, to help assess when to start.

Lifting2026.01.28

Thread lifting: choosing the thread type is not enough if the sequence is wrong

Thread lifting pulls tissue, while device-based lifting tightens it. When combining them, the order and interval influence the outcome. Here are the principles for choosing thread lifts and combining treatments.

Fillers2026.01.21

How to choose a filler clinic: 3 design principles

The same amount of filler can produce different results depending on placement, depth, and injection order. Here are three planning principles intended to reduce filler complications.

Volume2026.01.14

Are collagen injections better than fillers? Filling versus building

Fillers replace volume, while collagen-stimulating injections encourage your skin to produce collagen. We explain how they work, how long they last, and when to combine them.

Volume2026.01.07

Botox side effects: is the dose really the cause?

An unnatural expression after botulinum toxin treatment is usually a matter of balance rather than dose alone. Using treatment of frown lines as an example, this column explains how to preserve muscular balance.

Volume2025.12.31

Skin Botox: how does it differ from conventional Botox?

Skin Botox uses tiny divided doses in the superficial dermis rather than the muscles. This article explains why it is used for pores and skin texture, and how it differs from conventional Botox.

Skin boosters2025.12.24

Skin boosters: what is the difference between Rejuran and Juvelook?

Rejuran uses PN to support regeneration, while Juvelook uses PDLLA to stimulate collagen production. We explain how to choose between skin boosters with different goals.

Skin boosters2025.12.17

Hydrating skin injections: why do my results fade so quickly?

The duration of skin-hydration injections varies between people, even with the same treatment. This column explains how product, injection depth and skin condition affect longevity, and how to plan intervals.

Skin boosters2025.12.10

Skin boosters: can you inject more in a single session?

There are reasons to divide skin booster treatment into sessions rather than inject a large amount at once. This article explains Rejuran treatment intervals and when results develop.

Skin boosters2025.12.03

When I recommend glutathione injections before other procedures

Skin-treatment results can also be affected by how you feel that day. We explain when intravenous nutrient treatments, such as “Baekok” and “Cinderella” injections, may be considered before a procedure.

Pigmentation2025.11.26

Stronger laser for melasma? When it can make pigmentation darker

More laser sessions do not automatically lighten melasma. This column covers wavelength and energy selection, how to read skin responses, and care to reduce recurrence.

Pigmentation2025.11.19

Lasers for facial redness: why repeated toning may not help

If facial redness is caused by blood vessels rather than pigment, laser toning will not reduce it. This article explains how we distinguish redness-related concerns and vascular laser treatment.

Pigmentation2025.11.12

Post-acne pigmentation: wait or treat? 3 signs to guide the decision

Some post-acne pigmentation fades over time, while other marks need treatment. Learn the criteria for deciding when to begin laser treatment for pigmentation.

Skin2025.11.05

What happens if you undergo a procedure with a damaged skin barrier?

Adding a procedure while the skin barrier is impaired can delay recovery. This column explains how to distinguish sensitive skin from underlying dryness and decide when the skin is ready for treatment.

Acne2025.10.29

Red acne marks, scars or pigmentation: how to distinguish the three

Red acne marks, brown pigmentation, and depressed scars each require different treatment. This article explains how to distinguish these three types and plan treatment order.

Skin2025.10.22

Why pore lasers rarely solve everything in one session: an honest explanation

Enlarged pores involve stretched structures that do not return to their original state after one treatment. Learn how sebum-related and loss-of-elasticity pores differ and how treatment sessions are planned.

Skin2025.10.15

Acne scars: is resurfacing enough? Why I also focus on rebuilding

For depressed acne scars, rebuilding the dermis is a safer direction than simply removing the surface. This column explains how scar lasers and regenerative procedures are combined.

Aftercare2025.10.08

After laser treatment: when can you wash your face?

A guide to cleansing, sun exposure, exercise, and saunas after laser treatment. Respecting the recovery period affects the outcome.

Aftercare2025.10.01

When to decide on filler dissolution: the 90-day framework

Filler settles over the 90 days following injection. This guide explains when swelling and bruising subside, when to check for adverse reactions, and when to consider dissolving, stage by stage.

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DOCTOR'S COLUMN

PINNED

Before you book an appointment, read this

ALL COLUMNS

Skin Botox: Do you really need it every three months?

Under-eye wrinkles and dark circles: can Rejuran I help?

Fat-dissolving injections: an honest look at Newbizu swelling and recovery

Inflammatory acne: Gold PTT treatment frequency and intervals for reducing recurrence

Calf Botox: when to treat muscular calves

Rejuran in Cheongdam: how many days do swelling and bruising really last?

Ultherapy and Thermage together: do their effects overlap?

Laser toning near Gangnam Station: why one session may not clear pigmented spots

Sofwave: how it works, results and how long they last

Ultherapy in Gangnam: why does the shot count vary between clinics?

Eye Thermage for fine lines: how does it differ from Thermage?

Skin boosters compared: Rejuran, Juvelook or Rituo?

Pore reduction: How to choose Potenza, pico-fractional laser, or skin Botox

Hydrating skin injections and SKINVIVE: what is the difference?

Nasolabial folds: can Mihee injections replace fillers?

ONDA lifting for a sagging double chin

Skin Botox: can it really reduce the appearance of pores?

Radiesse and Sculptra: how do these collagen boosters differ?

Rituo: which skin types is it suited to, and how many sessions are needed?

Facial lifting: When should you start?

Lip filler: Amount and design for a natural-looking result

Lasers for melasma and pigmented spots: how do they differ from toning?

Potenza: why is it often recommended for pores and scars?

Temporalis Botox: How does it differ from masseter Botox?

AestheFill in Gangnam: Realistic expectations for collagen-booster duration

Acne scars: 3 things to check before CureJet treatment

Pico toning: why does melasma pigmentation return?

Small acne bumps: why extraction and anti-inflammatory injections may not be enough

Forehead fillers in Gangnam: principles for a natural contour

Facial redness: why do visible vessels worsen every summer?

Hyperhidrosis: how long does Botox last for sweaty palms and underarms?

When do exosomes begin to show their regenerative effects?

Why alternate Juvelook and Rejuran treatments?

Masseter Botox: when do results appear and how long do they last?

Stem cell treatments for skin regeneration: 2 things to know beforehand

Can Sculptra improve volume and firmness together?

Scar lasers: which treatment is right for me?

Under-eye hollows: fillers or Rejuran I?

Rejuran: an honest guide to recovery and treatment sessions

Fillers: is filling selected areas enough?

Choosing a thread-lifting clinic: advice after three disappointing treatments

More filler for nasolabial folds is better? Why a doctor may advise against it

No change after ten pico-toning sessions? A doctor explains possible reasons

Adult acne at work: is Gold PTT the answer? 3 honest answers

Ice packs for Ultherapy pain? Why a doctor may not recommend them immediately

Why I opened a solo-doctor clinic despite everyone’s advice against it

Under-eye fillers: ignoring the type of dark circle can make it look darker

Why I leave the final 0.1 cc: finishing facial asymmetry treatment

Ultherapy or Thermage: what is different, and do you need both?

Sofwave: 4 situations when a doctor may advise against it

ONDA lifting intervals: is more frequent better? First distinguish fat from sagging

Facial sagging: is it time to start lifting treatments? 4 signs

Thread lifting: choosing the thread type is not enough if the sequence is wrong

How to choose a filler clinic: 3 design principles

Are collagen injections better than fillers? Filling versus building

Botox side effects: is the dose really the cause?

Skin Botox: how does it differ from conventional Botox?

Skin boosters: what is the difference between Rejuran and Juvelook?

Hydrating skin injections: why do my results fade so quickly?

Skin boosters: can you inject more in a single session?

When I recommend glutathione injections before other procedures

Stronger laser for melasma? When it can make pigmentation darker

Lasers for facial redness: why repeated toning may not help

Post-acne pigmentation: wait or treat? 3 signs to guide the decision

What happens if you undergo a procedure with a damaged skin barrier?

Red acne marks, scars or pigmentation: how to distinguish the three

Why pore lasers rarely solve everything in one session: an honest explanation

Acne scars: is resurfacing enough? Why I also focus on rebuilding

After laser treatment: when can you wash your face?

When to decide on filler dissolution: the 90-day framework

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