Nd:YAG vs. Alexandrite: Which Actually Works?

"Doctor, I've Had 8 Sessions — Why Is My Hair Still There?" — A Question I Got Yesterday

Let me start with the bottom line.

The people who leave the most satisfied reviews for Nd:YAG laser hair removal

are mostly those who came to us after seeing little to no results elsewhere.

In this post, I'll walk you through exactly why that is.

What Makes Nd:YAG Different from Other Laser Hair Removal Options

Nd:YAG laser hair removal uses a 1064nm wavelength

to penetrate deep into the hair follicle.

Unlike Alexandrite (755nm),

Nd:YAG has lower melanin absorption —

but it reaches significantly deeper into the skin.

That's why it tends to work much better on thick, deeply rooted follicles,

particularly for beard hair removal and the bikini line.

Why Some People See No Results After 8 Sessions of ALEX

Honestly, this is something I hear two or three times a week in my consultation room.

Last week, a 28-year-old male patient came in.

He had completed 8 sessions of beard hair removal at another clinic,

was told "the area under the chin just isn't responding" and was offered an additional package —

so he came to us for a second opinion.

What I noticed was straightforward.

The device used at his previous clinic was Alexandrite only.

But his beard type had thick, deeply rooted follicles —

meaning the 755nm wavelength simply wasn't delivering enough energy

to reach the base of those follicles.

Nd:YAG at 1064nm reaches the deeper layers of the dermis —

approximately 4 to 6mm beneath the skin surface.

Alexandrite typically reaches about 2 to 3mm.

For patients with deeply rooted beard follicles,

that 2 to 3mm difference is what determines the outcome.

So my recommendation to him was:

"Don't add more sessions of the same wavelength.

Let's try 5 to 6 sessions of Nd:YAG instead."

In clinical practice, cases like his typically see

hair density drop to less than half by around sessions 5 to 6.

That said, it's not all upside.

Deeper penetration comes with more Pain.

If Alexandrite feels like "a rubber band snap,"

Nd:YAG is closer to "a sharp, hot needle pressing in."

That's why we always apply

cooling spray plus 30 minutes of topical anesthetic cream before every procedure.

Skip those steps, and patient satisfaction drops noticeably.

We also need to talk about side effects.

Because Nd:YAG energy penetrates deeply,

improper settings can lead to burns or post-inflammatory hyperpigmentation,

and some patients experience folliculitis that persists for one to two weeks after the procedure.

It usually resolves within a few days,

but without proper Aftercare, it can leave a Scar.

So — Who Is Actually a Good Candidate for Nd:YAG Laser Hair Removal?

Here's a quick breakdown.

Last month, a 33-year-old woman came in

asking specifically for Nd:YAG to remove fine vellus hair on her legs.

I turned her away that day.

Fine vellus hair responds well to Alexandrite in just one or two sessions —

there's no reason to put her through the Pain of Nd:YAG.

At another clinic, she might have been sold a package on the spot,

but this simply wasn't the right case for Nd:YAG.

My honest advice was: "Don't get this procedure here — find a nearby clinic and go with Alexandrite."

One misconception I see often in patient reviews:

the idea that "Nd:YAG is a better device than ALEX."

It's not better or worse — it serves a different purpose.

If it doesn't match your hair type,

you'll end up paying more and enduring more Pain for nothing.

If You've Read This Far, Here's What You're Probably Wondering

Q1. Some reviews say they saw results after just 1 or 2 sessions — is that actually possible?

That's a fair question, and the answer takes a little unpacking.

In my experience, patients who genuinely feel a noticeable reduction after 1 to 2 sessions

are roughly 2 or 3 out of every 10.

Most patients start noticing in the mirror — "wait, there's actually less there" —

around sessions 3 to 4,

and hearing comments like "haven't you been growing your beard out?" from others

usually starts around sessions 5 to 6.

Early reviews tend to be dramatic and eye-catching,

which sets expectations unrealistically high —

but given the hair follicle growth cycle, dramatic results that early simply aren't physiologically possible in most cases.

There's a closely related question that comes up alongside this one.

Q2. Nd:YAG costs more than ALEX — is it actually worth it?

This really depends on your specific situation.

If you've completed 6 sessions of ALEX and you're satisfied with the results,

there's no reason to switch to Nd:YAG.

But if you've had 8 sessions of ALEX

and the area under your chin looks exactly the same,

then 5 to 6 sessions of Nd:YAG will deliver far better value for money

than adding another ALEX package.

When I explain costs to patients, this is honestly the hardest part —

because the most wasteful thing you can do

is keep spending money on a procedure that isn't working for your hair type.

And finally — this last point is one you don't want to skip.

Q3. How common are side effects like folliculitis or burns after the procedure?

I'll be honest — I used to think they were fairly rare,

but in reality, mild folliculitis appears within about a week of the procedure

in roughly 1 or 2 out of every 10 patients.

It resolves on its own within a few days in most cases.

But here's the critical part:

using a sauna, doing intense exercise, or shaving on the day of the procedure

are the fastest ways to turn folliculitis into a lasting Scar.

Burns and post-inflammatory hyperpigmentation are a settings issue —

which is why it matters that your provider adjusts the energy parameters

to match your skin tone and hair type.

If a clinic rushes through every session on a single fixed setting,

that's worth questioning before you commit.

If you take one thing from today's post — for follicles that didn't respond to ALEX, 1064nm depth is the answer.


In the next post, I'll cover 'From the day of your Nd:YAG procedure through the first week — how to prevent folliculitis from getting worse.'


I'll show you through real cases where the difference between a clean recovery and a lasting Scar actually comes from.


This has been Dr. Wi Young-jin.