Written by Dr. Wi Young-jin of BeautysDoctors.

💡 Please read this before your appointment

Q. Doesn't GentleMax give the same results no matter where I go? It's the same machine, right?

A. Even with the same machine, the results and the likelihood of side effects vary dramatically depending on how the 755nm and 1064nm wavelengths are combined and how the energy levels are configured.

Q. Are side effects caused by having sensitive skin?

A. The primary cause is using the wrong wavelength and energy settings for your skin type. Even sensitive skin can be treated safely with the correct parameters.

"At Beautystone Clinic, we deliver more effective laser hair removal through personalized energy settings tailored to each skin type and strategic alternation between 755nm and 1064nm wavelengths."
— Dr. Wi Young-jin (Beautystone Clinic, Seoul)

Side effects aren't created by the machine — they're created by the settings

"I read a review where someone got burns from GentleMax."

"I've had three sessions and not a single hair has fallen out."

These are comments I hear all the time in my consultation room.

In both cases, the machine being used is the exact same GentleMax Pro Plus.

But here's the critical point.

GentleMax operates on two distinct wavelengths.

The 755nm Alexandrite wavelength,

and the 1064nm Nd:YAG wavelength.

These two wavelengths differ entirely in their depth of penetration and their rate of melanin absorption.

The 755nm wavelength is absorbed by melanin

in the superficial layers of the skin at a much higher rate.

This makes it highly effective for lighter skin tones with dark, coarse hair.

However, when used on darker or tanned skin,

the skin itself absorbs the energy,

which can lead to burns and post-inflammatory hyperpigmentation.

The 1064nm wavelength penetrates deeper beyond the melanin layer,

and because the skin absorbs it at a much lower rate,

it is significantly safer for darker skin types.

However, because the energy disperses more broadly,

it may be less effective when used on lighter skin tones.

Honestly speaking,

many clinics apply a single fixed wavelength setting

to every single patient in the same way.

It's a volume-driven model that prioritizes speed.

And that is precisely where side effects begin.

755nm 알렉산드라이트 파장과 1064nm Nd:YAG 파장 비교 설명

So what's the right approach?

For every new patient I see,

I always begin by assessing their skin type.

I use the Fitzpatrick Skin Type scale —

a classification system that categorizes skin tone from Type I through VI.

For lighter skin tones (Type I–III), I prioritize the 755nm wavelength.

For medium to darker skin tones (Type IV–VI), I increase the ratio of 1064nm

or alternate between both wavelengths.

I also carefully calibrate the energy settings —

specifically the fluence, which refers to the energy density per unit area —

starting conservatively and adjusting upward based on skin response.

Every case is different, but this is my standard approach.

Even on the same body, the inner thigh and the outer calf

differ in skin thickness and hair density,

so I set the parameters separately for each treatment area.

It takes more time and effort, I'll admit.

But this is the only way to achieve optimal results

without side effects.

👨‍⚕️ Key Takeaway from Dr. Wi Young-jin:

The vast majority of GentleMax side effects are not caused by the machine itself,

but by wavelength and energy settings that fail to account for the patient's skin type.

Alternating between 755nm and 1064nm based on skin tone and hair characteristics

is the cornerstone of safe and effective laser hair removal.

How I determine the right wavelength for your skin

This is one of the most common misconceptions I encounter —

the belief that "darker skin cannot undergo laser hair removal"

is only half true.

Proceeding with the 755nm wavelength without proper assessment can indeed be risky,

but with 1064nm set at an appropriate energy level,

laser hair removal can be performed safely and effectively.

We've had quite a few patients who saw no results after 10 sessions elsewhere,

yet achieved satisfying outcomes after just 2 to 3 sessions at Beautystone Clinic.

In most of those cases, the wavelength chosen had simply not been suited to their skin type.

That said, it's not all straightforward.

The 1064nm wavelength does produce results more gradually.

Its per-session efficacy can be lower compared to 755nm,

which may mean a greater number of sessions is required overall.

However, completing a consistent course of treatment without side effects

is ultimately the faster path to your goal — of that I'm certain.

Category	755nm (Alexandrite)	1064nm (Nd:YAG)
Suitable Skin Tone	Lighter skin (Type I–III)	Medium to darker skin (Type IV–VI)
Melanin Absorption Rate	High	Low
Depth of Penetration	Superficial (epidermis to upper dermis)	Deep (into the deeper dermis)
Per-Session Hair Removal Efficacy	High	Relatively lower
Risk of Side Effects (Darker Skin)	Risk of hyperpigmentation and burns	Low
Optimal Use	Alone or alternated with 1064nm	Alone or alternated with 755nm

Frequently Asked Questions

Q1. Do I need to shave the night before my laser hair removal session?

A. Yes — shaving on the day of or the evening before your session is recommended.

When hair is left long, laser energy gets absorbed by the surface of the hair shaft

rather than reaching the follicle.

This reduces efficacy and can generate unnecessary heat at the skin surface.

That said, if your skin is particularly sensitive immediately after shaving,

it's important to allow sufficient time for the skin to calm down before the procedure.

Q2. I developed hyperpigmentation after my GentleMax session. Will it go away?

A. In most cases, it resolves naturally.

The pigmentation typically fades within 4 to 8 weeks,

and diligent sun protection will help speed up the recovery.

However, if the hyperpigmentation persists,

it's essential to consult with your doctor before your next session.

Continuing with the same settings can cause the pigmentation to worsen.

This is a clear signal that the wavelength and energy parameters need to be reassessed.

Q3. Can I undergo laser hair removal while pregnant or breastfeeding?

A. I do not recommend it during pregnancy.

While laser energy has not been definitively proven to pose a direct risk to the fetus,

the skin during pregnancy is highly reactive due to hormonal changes,

and the risk of post-inflammatory hyperpigmentation is significantly elevated.

For those who are breastfeeding, suitability varies depending on individual circumstances,

so I encourage you to come in for a personal consultation.

We always recommend a thorough discussion before proceeding with any procedure.

This has been Dr. Wi Young-jin.

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