What is Laser Hair Removal?
Laser Hair Removal is a medical procedure that uses a concentrated beam of light (laser) to remove unwanted hair.
During laser hair removal, a laser emits a light that is absorbed by the pigment (melanin) in the hair.
The light energy is converted to heat, which damages the tube-shaped sacs within the skin (hair follicles) that produce hairs.
This damage inhibits or delays future hair growth.
Although laser hair removal effectively delays hair growth for long periods, it usually doesn’t result in permanent hair removal. Multiple laser hair removal treatments are needed for initial hair removal, and maintenance treatments might be needed as well.
Laser hair removal is most effective for people who have light skin and dark hair, but it can be successfully used on all skin types.
Why it's done?
Laser Hair Removal is used to reduce unwanted hair. Common treatment locations include legs, armpits, upper lip, chin and the bikini line. However, it’s possible to treat unwanted hair in nearly any area, except for the eyelid or surrounding area. Skin with tattoos should not be treated either.
Hair colour and skin type influence the success of laser hair removal. The basic principle is that the pigment of the hair, but not the pigment of the skin, should absorb the light. The laser should damage only the hair follicle while avoiding damage to the skin. Therefore, a contrast between hair and skin colour — dark hair and light skin — results in the best outcomes.
The risk of damage to the skin is greater when there is little contrast between hair and skin colour, but advances in laser technology have made laser hair removal an option for people who have darker skin. Laser hair removal is less effective for hair colours that don’t absorb light well: grey, red, blond and white.
How it Works?
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, hair 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 colour.
There are two types of melanin in the hair. Eumelanin gives hair brown or black in colour, while pheomelanin gives hair blonde or red colour. Because of the selective absorption of photons of laser light, only hair with colours such as black, brown, or reddish-brown hair or dirty blonde can be removed.
White hair, light blonde and strawberry blonde hair do not respond well. The laser works best with dark coarse hair. Light skin and dark hair are an ideal combination, being the most effective and producing the best results.
Comparisons with other Hair Removal Techniques
Comparison with Shaving
Shaving is a technique in which one removes hair from the skin with a razor. Shaving has been popular as a temporary hair removal technique since at least the 1700s.
Shaving, however, is only temporary and can lead to irritation of the shaved area.
Comparison with Waxing
Waxing is another option for hair removal. This method is an efficient way of removing hair; it is longer-lasting than shaving but not permanent.
Number of Sessions
Hair grows in several phases (anagen, telogen, catagen) and a laser can only affect the currently active growing hair follicles (early anagen). Hence, several sessions are needed to damage the hair in all phases of growth and force it to revert to a vellus non-coloured small hair.
Multiple treatments depending on the type of hair and skin colour have been shown to provide long-term reduction of hair. Most patients need a minimum of eight treatments.
Current parameters differ from device to device but manufacturers and clinicians generally recommend waiting from three to eight weeks between sessions, depending on the area being treated.
The number of sessions depends on various parameters, including the area of the body being treated, skin colour, the coarseness of the hair.
Coarse dark hair on light skin is the easiest to treat. Certain areas (notably men’s faces) may require considerably more treatments to achieve desired results.
The laser does not work well on light-coloured hair, red hair, grey hair, white hair, as well as fine hair of any colour, such as vellus.
Typically the shedding of the treated hairs takes about two to three weeks.
These hairs should be allowed to fall out on their own and should not be manipulated by the patient for certain reasons, chiefly to avoid infections. Pulling hairs after a session can be more painful as well as counteract the effects of the treatment.
Side Effects and Risks
Some normal side effects may occur after laser hair removal treatments, including itching, pink skin, redness, and swelling around the treatment area or swelling of the follicles.
These side effects rarely last more than two or three days. The two most common serious side effects are acne and skin discolouration.
Some level of pain should also be expected during treatments.
Numbing creams are available at most clinics, sometimes for an additional cost. Some numbing creams are available over the counter. Typically, the cream should be applied about 30 minutes before the procedure. Icing the area after the treatment helps relieve the side effects faster.