How does Laser Hair Removal work?

The laser light passes through the skin, but when it comes to a dark pigmented hair, that light turns to heat. The darker a hair is, the hotter it will heat. That hot hair is what essentially cooks the lining of the hair follicle and destroys structures that allow the hair to grow, that is, certain cells and the blood supply found at the base of every hair follicle. This heating process only works on hairs that are actively growing. Since only 15-30% of your hair is actively growing at one time, it is necessary to wait for another batch of treatable hair to come into that “magic moment,” that treatable phase, before doing the next treatment.

The hair you see growing when you start your treatments may represent only one third of the hair follicles you own. That is, you may have three times as much hair growing potential than you actually see as hair present on the skin surface at any one time.

Hair sticks tight in the follicle even after it stops actively growing. A laser treatment of hair that is present in the follicle, but not actively growing anymore, will not give optimal results. Why? This is because once the hair is not actively growing anymore, it starts pulling away from the base of the follicle. It is no longer in contact with the cells in the base of the follicle that generate hair growth, nor the blood supply at the base of the follicle. That means that hot little hair is not touching the lower parts of the follicle, those parts that are critical to hair growth. Depending on how low the hair might still be sitting, the follicle may be partially treated. This means that hair will still grow, but it will be smaller in diameter and lighter in color.

If the hair is close to the shedding stage, or the follicle is empty of hair at the time of the treatment, the laser treatment will have no effect on those follicles.


How much of my hair is in the actively growing, treatable, “magic moment” stage at one time?


This depends greatly on the area of the body. Generally, 20% of your hair is in the actively growing stage at one time. The sides of the bikini area have 30% of the hair actively growing at one time. Sometimes only 10-15% of the facial hair is actively growing at one time. What does this mean? The sides of the bikini can be completed in fewer treatments than most other body parts, and facial hair may require more treatments than areas on the body.


How close can laser treatments be spaced?

Hair is most susceptible to laser treatment when it first starts growing. Ideally, every hair should be treated as soon as it breaks the surface. This may not be practical time-wise or money-wise. Therefore, you should wait until the next batch of hair just starts to grow in. For the face and neck, this will be every 3-4 weeks. The hair on the body grows much more slowly. Treatments on body areas are usually best done every 6-8 weeks.


Is laser hair removal permanent?

It is certainly WAY more permanent than waxing, threading and tweezing. It is as permanent as electrolysis. Will you never see a hair grow again in a treated area? It is very likely that you will not. You certainly should not have laser hair removal in any area where you might want hair again!

On the underarms, for example, a few random fine, light colored hairs can crop up even after a series of 5 to 8 treatments is completed. Touch-up treatments at a nominal charge will eventually totally clear this area of any dark hair. Any white hairs will remain untouched.

Legs can be effectively cleared of dark hairs, although occasional hairs will appear, even after 5-8 treatments are completed. This is because hair follicles on the legs can remain dormant (and untreatable) for up to two years. However, if you persist with touch-ups, you can be entirely dark hair free. You may have some fine, colorless hairs that are noticeable in bright sunlight. The best option for these is to shave them.

One beauty of laser hair removal on the legs is that the skin is free of the little dots of hair seen in the follicles. Look at your legs after you have just shaved. You will see little dark spots where each hair is below the skin. If you have black hair, your skin will have very noticeable polka dots. After laser hair removal is completed, not only is stubble a thing of the past, but those little dots are gone.


How many treatments will I need?

This is a tough question. Most patients will need 5-8 treatments to completely clear an area. These are the factors that might require more treatments:

Facial hair on peri-menopausal and post-menopausal women. This is because the ovaries, the primary estrogen factories for women are not as frisky as a woman approaches menopause, and after menopause, they shut down altogether. A woman is left with what her fat cells might produce for her, and that is miniscule compared to what her ovaries produced. That little bit of testosterone she always had is no longer overpowered by the presence of estrogen. With the more dominant influence of testosterone, hair follicles that never grew a hair before, start maturing and growing hair. Fine, angel fuzz hairs start maturing into coarser, more pigmented versions of their earlier selves. For this reason, removing unwanted facial hair on women can be a prolonged project. Some patients start to view it as maintenance rather than a cure. Still, it is the most satisfactory way to deal with this kind of unwanted hair. Even if the hair is not completely eliminated, it is far finer, lighter and sparser than it would have been without treatment. Hormone imbalances. This is actually quite rare. However, women with polycystic ovary disease, women who have had to take certain kinds of chemotherapy, untreated thyroid conditions, women who have been on DepoProvera for birth control or to control cysts or endometriosis, for example —these sorts of things can cause unwanted hair to start growing. Genetic predisposition. This is the cause of most unwanted hairiness. Certain ethnic groups are more prone to hair growth than others. Some families just have hairier bodies and faces. Men. Testosterone causes hair to grow and men have a lot of it. Nevertheless, unwanted hair on the back, chest, ears, nose and other areas can all be successfully treated.


What if I have dark skin?

If you have unwanted dark hair, and relatively LIGHT skin, you are a good candidate for Cindy’s Candela GentleLase laser. There is no better laser than the Candela GentleLase for treatment of this ideal combination.

However, patients with darker than Asian or light Hispanic  skin coloring will be more safely treated with a different type of laser, such as a Light Sheer, which has the capability to keep the surface of darker skin cool while it heats the dark hair beneath.  A 1064 Yag laser is another option for hair removal on dark skin, because the longer wave length is more skin-sparing. 


What if I am tan?

If you are tan, you need to wait until your tan fades completely before you have laser hair removal. Even the lasers designed to treat darker skins are not that safe on tanned skin. The problem is that the pigment on the surface of your skin is absorbing the laser light and getting hot. You can get burned. The skin will scab and when the scab falls off, your tan will be gone in that spot. Eventually, the pigmentation will even out, but meanwhile, your skin looks pretty weird. You want to avoid this scenario.


What are the side effects?

1. Hyper-pigmentation. This is a rare side effect, but it is always TEMPORARY. Still it can look pretty weird, too. It can take from a couple weeks to one year after your last treatment to resolve completely. Protecting the treated area from sun exposure after a treatment can greatly reduce the risk of hyper pigmentation. However, some areas of the body, like underarms and bikini areas, are more prone to this side effect, even in the absence of sun exposure. Hyper pigmentation looks like a light colored bruise or like the hyper pigmentation seen with birth control pills or the mask of pregnancy. Although not desirable, most patients that the benefits of laser hair removal far outweigh the inconvenience of temporary hyper pigmentation. Not every patient experiences hyper pigmentation, and it is very minimal in most of those who do experience it.

2.  Hypo-pigmentation. This is not common, but it can happen if too much tan is present when a treatment is done. Again, this is temporary. Your skin tone will even out in time.

3.  Redness and swelling. This is a good sign. That means that the treatment was effective. The laser heated the hair enough to cause redness. Also, the hair was hot enough that fluid from the tissues was pulled into the hair follicles, making little bumps over the hair follicles. This redness and swelling (little bumps) disappear in a few minutes. More sensitive skin may stay red for a couple hours. Extremely sensitive skin may stay red and irritated for up to two days.

4.   Infection. If you get a blister or a scab from a laser treatment, which will not happen unless you are too tan, and you pick at it with less than clean hands, it is possible to get the area infected.

5.  Scarring. See number 4. There are those of us who are “pickers.” We know if we are one of these. Scars do not happen unless one picks at a blister or scab and gets it infected. The way to treat any break in the skin from a laser treatment is to keep it clean, do not pick at it, and apply an anti-biotic ointment. If treated in this fashion, no scarring will occur.

6.  Folliculitis.  Very rare. For some reason, the hair follicles look red, inflamed and irritated three days or longer after your treatment, when even the most sensitive skin will have settled down. When this happens, call Cindy. She will get you a prescription for an antibiotic cream, such as Cleocin, and the condition will clear up promptly. This condition is more common on the bikini and inner thighs than anywhere else.


Does laser hair removal work on blonde or white hair?

No. Laser hair removal will work on medium brown hair, but it will take more treatments than dark hair, because it does not heat as well. White hair lasers are so ineffective that you are far better off having electrolysis. White hair just does not heat up well with lasers, even when radio frequency energy is added.

Laser hair removal does not work on red, auburn, gray, white and blonde hair. For these hair colors, it is best to see a registered electrologist. I recommend Mary Clifford, RE. Mary has 25+ years experience as a registered electrologist, and is a knowledgeable and professional provider. You can reach her at 415-892-7776.