Laser hair removal is the method of permanently removing or reducing hair using a process called Selective Photothermolysis.
Selective Photothermolysis refers to the process of killing a certain selected structure (in this case the hair follicle) using heat that is generated by a beam of light. It is selective, because the light is only absorbed by certain structures, in this case the hair stub that is located in the bulb of the hair follicle. In electrolysis, the hair follicle is destroyed by an electric current that is inserted into the follicle through a small needle.
Because laser hair removal works by creating heat through the absorption of a light beam, whether it works or not depends on how effectively that light is absorbed by the hair in the follicle.
The substance that absorbs this light energy is melanin, which is the brown pigment found in hair as well as skin. The best results are obtained when the hair is dark and thick, and surrounded by white skin. Waxing, tweezing or plucking, or using depilatories removes the hair from the follicle and this will make laser hair removal completely ineffective. Laser hair removal is also completely ineffective on blond, gray, or white hair and sometimes with lighter red hair as well. Small, finer hairs are difficult to remove with laser, but good results can often be obtained with shorter pulse-widths and higher fluence levels.
In order for laser hair removal to be effective, it is also extremely important to stay on schedule with the treatments.
Since the laser only affects hair that are in the active part of the anagen stage of hair growth, the practitioner will schedule your sessions according to this hair growth cycle. If you miss an appointment, you need to reschedule it within a week of when it originally was scheduled or you will probably have to start all your laser treatments over again, and you will be unhappy with the results.
For darker skinned people, such as Hispanic, middle-eastern, Asian, or black people, a long-pulsed or variable pulsed Nd:Yag laser will get better results, be less painful, and safer. This laser has the ability to distinguish between the melanin in the hair and the melanin in the skin, which results in more laser energy being delivered to the hair rather than being dissipated through the surrounding skin tissue.
Laser hair removal technology has been around for well over ten years now, and has proven itself to be a very effective method of removing or reducing unwanted hair permanently.