It's rare, but it does happen. A laser treatment meant to remove hair may lead to even more hair. (In the industry it's called paradoxical hypertrichosis.) But don't panic. Before you swear off laser hair removal forever--it is one of the most popular aesthetic treatments for a reason--we should look at why laser light can stimulate more hair growth and how we can prevent a bad outcome. Experienced laser hair technicians are aware of this issue and can take steps to prevent it. Experienced is key, as is the type of laser your practitioner uses.
First, let's look at how a laser removes hair.
The Strength of the Laser
Dark objects absorb light and light objects reflect light. This is the basis of laser hair removal. It's the melanin in our hair that gives it color and it's the darkness of the melanin that absorbs the light and the heat. Heat the melanin enough and the stem cells in the follicle die.
But you have to heat the melanin enough to destroy the stem cells without burning the surrounding skin. Hair must be heated to 65 degrees to destroy stem cells and anything below that temperature can actually stimulate more hair growth.
Yes, more growth.
We can use light to get more hair to grow where you want it, like on your head. (To stimulate hair growth, we use our medical-grade LED light on a specific wavelength.) And we can use light to destroy hair where you don't want it. The light wavelengths and techniques we use can create very different outcomes.
This is why the strength of the laser is important.
When a follicle is only heated to say, 45 degrees Fahrenheit, it actually gets stimulated to produce more hair. So a laser that doesn’t have the power to heat a follicle up to the right temperature can produce the opposite of the intended effect.
Lasers should be chosen based on skin type so we can heat the follicle enough without burning the skin. The laser we use at Lutétia is the most advanced on the market, an Alexandrite and Nd:YAG laser that can treat both dark and light skin and still produce enough heat to destroy the follicle.
It's important that your practitioner adjust the laser according to each patient's hair and skin types. Yet all too often, a laser is kept on the same setting for every patient regardless of hair and skin type. This is a big mistake.
The Experience of the Technician
So why do laser specialists not use the right settings? Sometimes we find that they get comfortable with a single setting and use that for every patient. It’s just easier.
Another problem is rapid heating can be a little bit painful so some operators end up changing the settings to make the procedure more comfortable. But then the lower setting doesn’t heat the hair enough.
If you do your research you can find an experienced operator who will evaluate your hair and skin before recommending a treatment. They may even tell you they can’t effectively remove a certain kind of hair. The laser just won’t be effective on it. This kind of honesty can be annoying but it can also prevent an increase in hair growth.
An experienced laser technician may suggest that certain hair is bleached with a different laser. It’s the next best solution for fine hair or white hair that might not be a good candidate for laser hair removal.
A good specialist can read your hair before starting the treatment.
This is what you want. Someone who pays attention to these details.