How Does Laser Hair Removal Treatment Work?

Laser hair removal treatment includes a laser that will emit heat energy, absorbs the light penetrates deep down the root of each hair strand and damages the follicle. Effective for most skin tones and hair types, this damaged follicle will not be able to produce any further hair for a long time, sometimes never.

The treatment is relatively safe, and there is minimum disruption on the skin surface. The procedure works best on people with dark hair and light skin. It does not work on hair that is gray, white, light red, light brown or blonde. Several treatments and sessions may be needed for long-term benefits and permanent hair removal.

Our skin is not adversely affected by the treatment because our skin cools down more quickly than the hair follicles. The treatment ends with the application of creams to cool down the skin and minimize the risk.

Hair removal treatments on face and under the arms are normally completed in about 15 minutes. The other area of the body will need at least one hour to complete the procedure.

The primary principle behind laser hair removal is selective photothermolysis (SPTL), the matching of a specific wavelength of light and pulse duration to obtain optimal effect on a targeted tissue with minimal effect on surrounding tissue. Lasers can cause localized damage by selectively heating dark target matter, melanin, thereby heating up the basal stem cells in the follicle which causes hair growth, the follicle, while not heating the rest of the skin. Light is absorbed by dark objects but reflected by light objects and water, so laser energy can be absorbed by dark material in the hair or skin, with much more speed and intensity than just the skin without any dark adult hair or melanin.

Melanin is considered the primary chromophore for all hair removal lasers currently on the market. Melanin occurs naturally in the skin and gives skin and hair their color. There are two types of melanin in hair. Eumelanin gives hair brown or black color, while pheomelanin gives hair blonde or red color. Because of the selective absorption of photons of laser light, only hair with color such as black, brown, or reddish-brown hair or dirty blonde can be removed. White hair, light blonde and strawberry blonde hair does not respond well. Laser works best with dark coarse hair. Light skin and dark hair are an ideal combination, being most effective and producing the best results, but lasers such as the Nd:YAG laser are able to target black hair in patients with dark skin with some success.[6][7]

Hair removal lasers have been in use since 1997 and have been approved for “permanent hair reduction” in the United States by the Food and Drug Administration (FDA).[7][8] Under the FDA’s definition, “permanent” hair reduction is the long-term, stable reduction in the number of hairs regrowing after a treatment regime. Indeed, many patients experience complete regrowth of hair on their treated areas in the years following their last treatment. This means that although laser treatments with these devices will permanently reduce the total number of body hairs, they will not result in a permanent removal of all hair.[9]

Laser hair removal has become popular because of its speed and efficacy, although some of the efficacy is dependent upon the skill and experience of the laser operator, and the choice and availability of different laser technologies used for the procedure. Some will need touch-up treatments, especially on large areas, after the initial set of 3-8 treatments.