How does the laser work in laser hair removal?

What keeps the hair from growing back? How does the laser target just the hair, and not the skin?

Answers from doctors (3)


Greenwich Medical Skincare and Laser Spa

Published on Jan 25, 2010

The laser can distinguish between the skin and the hair, and goes for the dark color. That's why the ideal candidate is a fair skinned person with dark (brown/black) hair. The area being treated should be shaved prior to treatment, so the laser can hit the hair in the follicle and not the outside hair. When the heat travels down the hair to the follicle the follicle is destroyed and unable to grow new hair. The hair grows in 3 cycles, not all hairs are growing at one time, therefore it takes multiple treatments for full hair removal.
None of the above is not intended as medical advice. If you have a medical concern, please consult your doctor.

//imgs-origin.edoctors.com/imageresizer/image/user_uploads/58x58_85-1/doctors/2398_1424803303.jpg
Answered by Greenwich Medical Skincare and Laser Spa

The laser can distinguish between the skin and the hair, and goes for the dark color. That's why the ideal candidate is a fair skinned person with dark (brown/black) hair. The area being treated should be shaved prior to treatment, so the laser can hit the hair in the follicle and not the outside hair. When the heat travels down the hair to the follicle the follicle is destroyed and unable to grow new hair. The hair grows in 3 cycles, not all hairs are growing at one time, therefore it takes multiple treatments for full hair removal.
None of the above is not intended as medical advice. If you have a medical concern, please consult your doctor.

Published on Jul 11, 2012


Esta Kronberg, M.D.

Published on Jan 14, 2010

The laser light is attracted to the darkness of the hair. This is why the best candidate is a light skinned dark haired patient.
It takes several treatments but gradually thins the hair with each treatment. The light goes down the hair shaft to destroy the hair bulb. The hair needs to be treated in a certain stage of the growing cycle. This is why it takes several treatments.

//imgs-origin.edoctors.com/imageresizer/image/user_uploads/58x58_85-1/doctors/2292_1421355456.jpg
Answered by Esta Kronberg, M.D.

The laser light is attracted to the darkness of the hair. This is why the best candidate is a light skinned dark haired patient.
It takes several treatments but gradually thins the hair with each treatment. The light goes down the hair shaft to destroy the hair bulb. The hair needs to be treated in a certain stage of the growing cycle. This is why it takes several treatments.

Published on Jul 11, 2012


Celibre Medical Corporation

Published on Jan 14, 2010

Laser hair removal works when the bulb (base) of the hair follicle is heated up to the point where it damages the blood vessel (the vein) that brings blood to the hair. Once this vein is damaged and no longer feeds blood to the hair, it will not regrow.

The heat from the laser light is concentrated at the base of the hair follicle because this is the darkest color within the skin. Laser (light) energy absorbs into dark colors very easily (similar to a black t-shirt on a sunny day). Because the base of the hair follicle is the
darkest area of the body, it absorbs most of the light and heat from the laser. The heat avoids the rest of the skin because it is lighter in color. This phenomenon is called "selective photothermolysis" or more simply selective heating.

//imgs-origin.edoctors.com/imageresizer/image/user_uploads/58x58_85-1/doctors/2507_1424468866.jpg
Answered by Celibre Medical Corporation

Laser hair removal works when the bulb (base) of the hair follicle is heated up to the point where it damages the blood vessel (the vein) that brings blood to the hair. Once this vein is damaged and no longer feeds blood to the hair, it will not regrow.

The heat from the laser light is concentrated at the base of the hair follicle because this is the darkest color within the skin. Laser (light) energy absorbs into dark colors very easily (similar to a black t-shirt on a sunny day). Because the base of the hair follicle is the
darkest area of the body, it absorbs most of the light and heat from the laser. The heat avoids the rest of the skin because it is lighter in color. This phenomenon is called "selective photothermolysis" or more simply selective heating.

Published on Jul 11, 2012


Related Questions for Laser Hair Removal

Laser Hair Removal -2 answers
How many sessions are typically needed for upper lip and chin hair removal?
See More
Laser Hair Removal -1 answer
Will the dark spots go away? And does the hair never grow back once you get the treatment?
See More
Laser Hair Removal -3 answers
I have discoloration & scars caused by ingrown hairs. How will the laser affect those areas? Make it worse? Clear or lighten?
See More
Laser Hair Removal -3 answers
Is this the best method for hair removal near the vagina?
See More
Laser Hair Removal -3 answers
Is laser hair removal safe and effective at this young age?
See More
Laser Hair Removal -5 answers
I would like to have my arms, legs, bikini area, underarms, butt, lower back and facial hair done. Can you do a full body Laser Hair Removal treatment in one setting?
See More
Laser Hair Removal -2 answers
I have an autoimmune disease and all of a sudden it hurts when I get my laser hair removal done. Before I was diagnosed with the disease, the laser hair removal never used to hurt
See More
Laser Hair Removal -2 answers
Is complete hair removal around the vagina safe?
See More
Laser Hair Removal -2 answers
Please advise if it is safe to breastfeed while undergoing Laser Hair Removal treatments?
See More
Get answers from our experienced doctors.
How it works
Laser Hair Removal -2 answers
If laser makes my skin darker in the first session will it become more dark session by session? I made one laser session of hair removal for pelvic area and I noticed that the skin has become darker than what it was previously. I want to know if I made another session if my skin will become more darker than it currently is?
See More
Laser Hair Removal -4 answers
I have thick coarse hair on my face.. under the chin and the sides of my face. Currently, I'm using a threading method to remove hair. My skin is olive and the hair is darker. Please advise. Can I get a permnant result and which laser is best for my skin.Thanks
See More
Laser Hair Removal -3 answers
I was just wondering if I was being told the truth that this would help my acne and acne scars? I have been reading on the subject and it seems like different types of laser treatment are needed for acne help.
See More
Laser Hair Removal -2 answers
I had the procedure done 2 days ago and now have burns and blisters on my legs.
See More
Laser Hair Removal -4 answers
Does this help?
See More
Laser Hair Removal -2 answers
I have faint black hair on my face and a pale skin color. I've heard that you need to shave before a treatment. Is that true? I don't really fancy shaving as I'm worried my facial hair will come out prickly.
See More
Laser Hair Removal -1 answer
A friend of mine had a scratch and after his LHR treatment the area around it looks burnt and is itchy. Should areas like that- moles and darker areas be masked in some way during LHR sessions?
See More
Laser Hair Removal -1 answer
I have been taking isotretinoin 20 mg for the past 4 months, can I undergo laser treatment for hair reduction while taking this dosage? Or, how long should I wait, after I stop taking isotretinoin 20 mg, before starting laser hair removal treatment?
See More
Laser Hair Removal -2 answers
Will using a laser hair removal laser near my tattoo remove or affect it? I don't want my tattoo to fade but the hair nearby it is thick and i'd like to have it removed.
See More
Get answers from our experienced doctors.
How it works

Related Articles

Have specific questions?
ASK A DOCTOR