Is laser safe for darker skin? The evidence, and what it means in South Korea

Why darker skin is treated differently

A laser does not see skin. It sees a chromophore, meaning whatever absorbs its wavelength, and it dumps energy into that.

In pale skin, the pigment in a sun spot is more or less the only thing competing for that energy. In Fitzpatrick IV to VI skin it is not. Melanin is spread through the whole epidermis, it absorbs broadly across the spectrum, and it takes up energy that was meant for the target underneath. The 2026 clinical review in the Journal of the American Academy of Dermatology states the consequence directly: that competing chromophore raises the risk of post-inflammatory hyperpigmentation, loss of pigment, blistering and scarring.

Everything else on this page follows from that one sentence.

What actually goes wrong, and how often

Two different things, and they get conflated constantly.

Post-inflammatory hyperpigmentation. A brown mark where the treatment was. It is the skin's pigment response to injury, not a burn. In a 2025 systematic review of 369 patients with skin of colour, all of them Asian and 58% of them Fitzpatrick IV or V, laser was the trigger in 95% of cases. Fractional CO2 was the single commonest device behind it, at 43%.

Loss of pigment. Pale spots where the treatment was. Rarer, discussed far less, and much harder to undo.

The first usually fades. The second may not. A clinic that quotes you a risk figure at consultation is almost always quoting the first.

The specific risk in South Korea: toning sold by the package

Laser toning is a Korean protocol: low fluence, large spot, many passes, repeated often. It is sold here in courses of ten, and travellers routinely compress a course into a short trip, because that is the only way it fits around a flight.

There is a study describing what happens at that pace. Twenty-three women with melasma were treated with a Q-switched 1064 nm Nd:YAG at 2.0 J/cm2, three times a week, for two months. All 23 developed visible mottled hypopigmentation. Thirteen were followed for four months afterwards with no further treatment, and none of them repigmented.

Those patients were Fitzpatrick III. If you are IV or V, that finding does not become gentler.

The author's conclusion was that toning more often than once every two weeks should be avoided. A package built to be finished inside a fortnight is a package built against that advice.

What the evidence says prevents it

The 2025 review tested the measures clinics actually offer: sunscreen, topical corticosteroids, epidermal growth factor, oral tranexamic acid, topical antibiotics, cooling air devices.

One of them worked consistently. In the authors' words, "only sunscreen consistently prevented the incidence of PIH; however, the severity of the ensuing PIH may be diminished with other measures."

The rest of that sentence is worth reading twice. The other measures may soften the mark once it appears; they did not reliably stop it appearing. And cooling air, the device blowing chilled air at your face during treatment that every patient reads as a safety measure, carried a relative risk of 2.6. More pigmentation, not less.

Strict sun protection before the appointment, not only after it, is the intervention with the best support behind it.

If it happens anyway, how long does it last

A review of 46 studies covering 1,356 people with skin of colour gives the honest numbers.

Topical retinoids brought partial improvement in 85% of people and laser in 66%. Laser was the only intervention that cleared it completely in a subset, 26%. But the timing is the part that matters to someone on a trip: mean time to resolution was 68 days when the pigmentation was left alone, and 140 days when it was treated with laser. Those patients had already carried the marks for a mean of 21 months before any treatment started.

So the realistic frame is months rather than weeks, and treating it is not obviously faster than waiting it out.

Your Fitzpatrick type is a starting point, not a measurement

The scale asks how your skin burns and how it tans. That is a proxy for melanin, and not a especially good one. It originally ran to type IV; types V and VI were added afterwards.

It is also unreliable in the room. In a survey of 472 patients and 20 providers, self-assessed type differed from the clinician's assessment by a mean of half a point, and clinicians tended to underestimate how readily their patients burned.

State your type at the consultation, then treat the answer as a question rather than as a setting.

What to settle before you book

• Which laser, at what fluence, and at what interval. The interval is the number most often missing from a package, and it is the number the toning evidence turns on.
• Whether the fluence is being lowered for your skin, and by how much. "We treat all skin types" is not an answer to that.
• Whether a test area is treated first, and how long the clinic waits before reading it.
• What happens if pigmentation appears after you fly home. Ask before you pay a deposit.
• Whether the plan can be spread across two trips. If the honest interval does not fit your trip, the schedule is the thing that should change.

The bottom line

Darker skin is not a contraindication to laser treatment. It is a reason for lower energy, longer gaps between sessions, and a clinician who will name both of those numbers without being pushed.

The failure mode here is not an exotic device. It is an ordinary device run too hot and too often, on a schedule shaped by a flight home.