Melasma, Sunspots and Post-Acne Pigmentation: Why One Laser Cannot Treat Them All

“Doctor, I have this dark spot. Can you just laser it off?”

I hear this question all the time.

And the first thing I usually do isn’t choose a machine.

I look at the spot and ask:

“What exactly is this pigmentation?”

Because melasma, sunspots, and dark marks after acne can have one obvious thing in common:

They all look brown.

But what’s happening underneath the skin can be very different.

And that’s why treating pigmentation is much more complicated than simply “removing the brown.”

Think of stains on three white shirts

Imagine three white shirts.

The first is stained with coffee.

The second with ink.

The third has been scorched by an iron.

From across the room, all three may simply look like they have a brown mark.

But you wouldn’t expect one stain remover to fix all three.

Your skin works in much the same way.

What our eyes see is color.

What we need to understand medically is the process that created that color.

Sunspots: A relatively straightforward pigment target

Sunspots, or solar lentigines, commonly appear on areas with years of accumulated sun exposure, such as the face and the backs of the hands.

Once the diagnosis is established, the treatment target is relatively clear:

Melanin.

This is why several laser and light-based technologies can be effective for appropriately selected sunspots.

I sometimes think of these lesions like pencil marks on paper.

We can identify the mark.

We know where it is.

And we have a reasonably clear idea of what we’re trying to remove.

But there’s an important step before treating any brown spot:

Make sure you know what it is.

Not every pigmented lesion is a harmless sunspot, and not every brown lesion should automatically be treated with a laser.

Diagnosis always comes first.

Post-acne pigmentation: The acne may be gone, but the inflammation left something behind

After an inflammatory acne lesion resolves, some people are left with brown or gray-brown marks.

We call this Post-Inflammatory Hyperpigmentation, or PIH.

The important words here are:

Post-Inflammatory.

The pigment developed as a consequence of inflammation.

Think of a small fire in a kitchen.

You put the fire out, but the wall is still covered in smoke stains.

The acne was the fire.

PIH is the stain left behind.

That means we need to think about two problems at the same time.

How do we fade the existing pigmentation?

And how do we prevent new inflammation from creating more?

If someone continues developing inflammatory acne while we only treat the pigmentation, we’re essentially cleaning smoke off the walls while the kitchen is still burning.

Melasma is a completely different story

Melasma is one of the reasons I’m particularly cautious when someone says:

“If it’s pigment, why don’t we just laser the pigment away?”

Because melasma isn’t simply a pile of melanin sitting in the skin waiting to be removed.

It is a chronic and complex pigmentary disorder influenced by multiple factors, including melanocyte activity, ultraviolet radiation, visible light, hormonal influences, and changes within the skin environment.

I like to think of melasma as an ink factory.

Imagine finding a pile of ink outside the factory.

You can clean it away, and everything may look better for a while.

But if the factory is still producing ink…

the problem eventually returns.

Certain laser and light-based treatments may have a role in selected patients with melasma.

But aggressively trying to “erase” melasma without controlling the biology behind it can lead to recurrence—and in some cases, more pigmentation following inflammation.

Why doesn’t a stronger laser mean faster melasma clearance?

This is one of the most important concepts I want patients to understand.

Pigment can absorb laser energy.

But the surrounding skin can also respond to heat and inflammation.

This is especially relevant in Asian and darker skin types.

If we create excessive inflammation, the treatment itself may trigger Post-Inflammatory Hyperpigmentation.

In other words:

We were trying to treat pigmentation…

and the treatment created new pigmentation.

I sometimes compare this to cooking.

If the food isn’t cooked yet, increasing the heat may help.

But that doesn’t mean turning the stove to its maximum setting will produce the best meal.

Sometimes you simply burn it.

In pigment treatment, more energy is not automatically better treatment.

So how do we choose the right laser?

I start with the diagnosis.

Then I ask several questions.

Where is the pigment located?

What is the biological target?

What is the patient’s skin type?

Is there active inflammation?

How likely is the condition to recur?

Only then should we start thinking about wavelength, pulse characteristics, energy delivery, and treatment parameters.

This is why two people who both say,

“I have dark spots,”

may receive completely different treatment plans.

We’re not simply treating the color our eyes can see.

We’re treating the biology that created the color.

What does the evidence tell us?

Different pigmentary disorders respond differently to treatment.

Solar lentigines may respond well to appropriately selected pigment-targeting lasers or light-based devices.

PIH management often requires controlling the underlying inflammation, photoprotection, topical therapy, and careful selection of procedures when needed.

Melasma usually requires a broader long-term strategy involving rigorous photoprotection and appropriate topical or systemic treatments, with lasers and energy-based devices playing a more selective role.

This is why I don’t believe there is one universal “pigmentation laser.”

The correct treatment depends on the diagnosis.

Dr. Ichkal’s Perspective

When a patient points to a brown mark and asks:

“Doctor, can you laser this off?”

My first answer usually isn’t yes or no.

It’s:

“Before we laser it, let’s understand what it is.”

Because in pigmentary medicine, the same color can come from completely different processes.

A sunspot may behave like a pencil mark on paper.

PIH may be the smoke stain left after a fire.

And melasma may behave more like a factory that continues producing ink.

Once we understand which problem we’re dealing with, choosing the treatment becomes much more logical.

For me, the goal of laser medicine isn’t to chase every spot of color we can see.

It’s to understand:

Why did that color appear in the first place?

Because sometimes what we see on the surface is only the final result of a much deeper biological process.