Paradoxical Hypertrichosis: When Laser Hair Removal Causes More Hair

Laser hair removal is one of the most widely performed cosmetic procedures in the world. Most people see a successful reduction of their unwanted hair. However, on occasion, some people grow excess hair post laser treatments. We hear a lot about paradoxical hypertrichosis in the electrology world. I have seen so many women in my career (myself included) who have had excess hair growth from laser hair removal in hormonal places like the face.

What Is Paradoxical Hypertrichosis?

Paradoxical hypertrichosis (PH) is the development of new, thicker or darker hair in an area that has been treated with laser or IPL. We are born with about 5 million hair follicles and the majority of those are tiny vellus hairs that are difficult to see. PH triggers those fine hairs to grow thick and coarse.

If you’re noticing hair that feels thicker or darker over time for other reasons too, our guide on why hair grows thicker and darker covers common causes beyond laser.

Who Is Most Likely to Be Affected?

Some of the strongest recurring risk patterns for PH are:

• Medium to darker skin tones
• Dark hair
• Hormonal or androgen-driven hair growth
• Possibly treatment over vellus/fine hair instead of coarse terminal hair

One study noted that they saw fewer instances of PH in clients who wore sunscreen daily, suggesting that sun exposure might also contribute.

Paradoxical hypertrichosis can happen for both men and women. The areas that we are most likely to see PH usually have androgen-driven hair growth. In men, that’s on the back and shoulders. For women it’s usually on the face, neck or upper arms.

How Common Is It?

Here’s what we know. The literature on PH is not consistent. Reported rates range from 0.34% to 10%, and I would hazard a guess that with the rise of at-home IPL machines the real numbers may be higher and be simply underreported.

The best information we have comes from a 2021 systematic review that looked at 22 studies involving 9733 patients. Researchers found that roughly 3 out of every 100 patients experienced PH, about 3%. The studies varied quite a bit, so the real risk is still hard to pin down. Early studies suggested rates from 0.6% to 10%, and newer studies found very different rates depending on who was being studied.

Bottom line: PH looks uncommon overall, but it may show up more often in certain high-risk groups.

What Causes PH?

We don’t exactly know what triggers it.

One idea I’ve read in a few places is that the laser hits a follicle with enough energy to stimulate biological activity, but not enough heat is applied to the area to kill off the hair follicle. Nearby vellus hairs may get stimulated during a laser session and then become thick and terminal.

Can It Be Treated?

The good news is that PH is not always permanent. Some studies have shown improvement with continued laser treatments using adjusted settings. That can make sense when a provider who understands PH is carefully changing energy, pulse, or technique, and when you’re still a good laser candidate for that area.

It is not always the right move to keep doing more of the same. If fine facial hair got thicker after laser or IPL, repeating the same approach can make things worse for some people. In those cases, pausing and reassessing is smarter than pushing through another package of identical sessions.

When the hair is persistent, especially on hormonal areas like the face, electrolysis is often a better option. Electrolysis treats each follicle directly, so it does not rely on pigment the way laser does, and it can permanently clear hairs that laser stimulated or left behind.

If This Happened to You

If you think laser or at-home IPL left you with more hair:

• Pause further laser or IPL on that area until someone experienced reviews what you’re seeing
• Avoid assuming you just need “stronger” settings without a plan
• Note which areas changed (face, neck, upper arms, and so on) and when you first noticed it
• Get a second look from a provider who offers both laser and electrolysis, so you’re not locked into one tool

You do not have to figure this out from internet forums alone. An in-person assessment goes a long way.

Ready to Talk Through Your Options?

If laser left you with more hair than you started with, or you’re unsure whether laser or electrolysis is the better next step, we’re happy to look at your skin and hair with you. Book a free consultation and we can talk through what makes sense for your goals.