Laser Hair Removal Basics

Many people ask us, "how does laser hair removal actually work?"  Well there a few basic concepts to consider when trying to  understand how a light-based technology (aka "the laser") can permanently remove/reduce unwanted hair.  


Many modern-day lasers utilize "IPL" technology, known as "Intense Pulse Light".  This basically means that a light source is used to target the hair.  In the system our medspa utilizes, the Palomar Starlux 500, a red light is filtered from the spectrum of white light, and this specific bandwidth of red light is targeted at the hair follicles.  


"How does the red light target just the hair, and not surrounding tissue," one may ask.  Well, all of us have a compound in our hair (and skin) called "melanin", which is responsible for the pigment found in hair (and skin).  Some of us have more of this pigment than others (such as brunettes vs. blondes).  Through years of research and development, scientists found that this red spectrum of light is highly attracted to melanin, or in more scientific terms, has an "affinity" to melanin.  The red light, moreover, is not attracted to other molecules found in tissue such as water for example, and thus doesn't harm those compounds.

This selective affinity to melanin has enabled and led to modern-day laser hair removal.  When the red light is applied to the skin via the laser machine, the laser's energy travels down the hair shaft to the follicle and essentially destroys the follicle.  There is a caveat to this, however.  The hair follicle must be in the "active" hair growth phase (known as the "Anagen" phase) in order for it to be affected by the laser's energy (for it to be destroyed that is).  Clinical studies show that only about 15-20% of our hair follicles are in this "active" phase at any given moment.  Therefore, as some of you may already know, several treatments are required to permanently remove hair in a given body area.

I mentioned above that the laser's light is attracted to "melanin", which is found in hair AND skin.  This fact raises a little but of a concern when treating darker-complexioned patients.  Since the laser does not discriminate between hair melanin and skin melanin, it can potentially mistake the melanin in the skin as its intended target.  If the laser technician is not careful or poorly-trained, he/she can cause damage to the patient's skin leading to irritation, hyper or hypo-pigmented areas, and even burns.  Because of this, darker-skinned patients and patients who have tans or sun burns should be cautious and lower energy settings should always be used to be safe.

This in a nut shell is how laser hair removal works.