Laser Hair Removal: How It Works & Does It Hurt?

Updated in March 2024

Laser hair removal is a cosmetic treatment indicated for permanent hair removal available for women or men. It can be done on the armpits, legs, groin, pubic area and beard.

This type of treatment uses beams of light that are converted into heat and absorbed by melanin, which is the hair pigment. It damages the hair root permanently, inhibiting hair growth.

Laser hair removal can be done with different devices that depend on the characteristics of the hair and skin tone. This method can eliminate more than 90% of the hair, requiring around 4 to 6 sessions to completely eliminate the hair in the treated area, followed by one annual session, as a form of maintenance.

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Where it can be used

Laser hair removal is recommended for permanent hair removal from areas of the body such as:

  • Legs and thighs
  • Arms and forearms
  • Hands and feet
  • Groin and pubic area
  • Buttocks and perianal region
  • Armpits
  • Chest or back
  • Abdomen
  • Neck

Laser hair removal can also be done on the face, including on the upper lip, the area between the eyebrows and the beard in men. It can also be done on the ears in cases of hirsutism. 

How laser hair removal works

Laser hair removal works by damaging the hair follicle that is in the anagen phase, which is the hair growth phase. This prevents or delays its growth.

When applied, the laser emits beams of light that are converted into heat. These are then absorbed by melanin, which is the pigment that gives the hair its color, and therefore, the results are better when the hair is darker.

Furthermore, because it acts on melanin, the skin should not be tanned before carrying out the session, as this increases the risk of skin burns.

Around 15 days after treatment, the hair becomes loose and falls out, giving a false appearance of growth, but this is easily removed in the shower with a skin exfoliation.

Does the laser work on gray, light or red hair?

Laser hair removal does not work on gray or light hair, as these do not contain much melanin. Therefore, this method of hair removal is not recommended in these cases.

Furthermore, although there are currently several laser devices available on the market, it may not be effective in people with red hair.

How to prepare

To prepare for laser hair removal, you should take some important precautions, such as:

  • Do not sunbathe or use artificial tanning for about 10 to 15 days before the session
  • Apply sunscreen daily, with at least SPF 30
  • Do not wax, tweeze or use electrolysis approximately 4 to 6 weeks before the procedure
  • Do not use products containing retinoic acid, glycolic acid or salicylic acid in the region to be treated, for 7 days before and after each session;
  • Do not use makeup on the day of the session, if the waxing is on the face
  • Inform the doctor or technician about the use of any anticoagulant medications, such as heparin, warfarin or acetylsalicylic acid, as these may need to be discontinued.
  • Drink plenty of water and use moisturizer in the days before treatment.

People who lighten their body hair can have laser hair removal, because the laser acts directly on the hair root, which is ultimately unaffected by any dyes.

In addition, you should shave your hair with a new razor or use depilatory cream 1 day before or on the day of the session.

How it is done

Laser hair removal is performed by a dermatologist or a cosmetic technician, using the following steps:

  • Clean the skin with 70% alcohol to remove any traces of oil or moisturizer
  • Put on protective glasses and offer protective glasses to the client
  • Shave the hair in the area to be treated, if the client has not done so before the session, or if the hair is inadequate in size for the laser application
  • Apply an anesthetic cream or gel to the area, if necessary, and wait a few minutes for it to take effect
  • Remove the anesthetic cream or gel from the skin
  • Apply the laser to the region to be treated

After each region is lasered, the skin can be cooled with ice, spray or cold gel, but most recent equipment contains a tip that allows the area to be cooled immediately after each laser shot.

At the end of each session, it is recommended to apply a soothing lotion to the treated skin.

How many sessions are needed?

The number of laser hair removal sessions varies according to skin and hair color, hair thickness and the size of the area to be waxed, with around 2 to 6 sessions generally required.

The interval between sessions may also vary according to the area. In area where hair grows faster, the interval may be 4 to 6 weeks, and for regions where hair grows slowly, the interval may be 12 to 16 weeks.

Does laser hair removal hurt?

During the laser hair removal session, it is normal to feel some pain and discomfort, as if there were a few bites in the area.

The thinner and more sensitive the person's skin, or the thicker the hair, the greater the chance of experiencing pain during hair removal.

In some cases, an anesthetic cream or gel may be applied to the area. However, its use should be avoided as pain and the sensation of intense burning in the skin are important parameters for the doctor to identify whether there is a burn, and thus better regulate the laser device.

How does the skin feel after the session?

After the first laser hair removal session, it is normal for the areas that previously had hair to become a little warmer and redder, indicating that the treatment was successful. This skin irritation disappears after a few hours.

After a treatment session you should take care of your skin to prevent it from becoming stained and dark.

Care after laser hair removal

After laser hair removal, some care is required, such as:

  • Apply a soothing lotion to shaved skin
  • Avoid exposing yourself to the sun or using artificial tanning between sessions
  • Use sunscreen daily, with at least SPF 30, and reapply whenever necessary
  • Avoid wearing makeup for at least 24 hours after laser hair removal on your face
  • Do not wax or pluck hair with tweezers during treatment

Furthermore, the use of a new razor or depilatory creams between sessions is permitted because they can preserve the hair roots, without compromising the treatment. 

Types of laser

There are different types of laser devices available, which include:

1. Diode

The diode laser uses a wavelength of 800 nm, which penetrates deeper into the skin. This type of laser causes less damage to the skin, and is suitable for all skin types, including darker skin.

2. Intense pulsed light

The intense pulsed light (IPL) laser is a device that emits flashes of light with a shorter wavelength, from 500 to 690 nm, which does not penetrate deeply into the skin, is less effective and requires more sessions.

This type of laser can be recommended for all skin types and for larger areas.

3. Nd:YAG laser

The ND:YAG laser (yttrium-aluminum-garnet laser doped with neodymium) uses wavelengths of 1064 nm, which penetrate the skin better, and is suitable for all skin types.

4. Alexandrite

The Alexandrite laser uses a wavelength of 755 nm, which has a good ability to penetrate the skin. This type of laser is considered to be effective, especially for lighter hair and fair or dark skin.

5. Ruby

The Rubi laser uses wavelengths of 694 nm, and is recommended for people with lighter skin and dark hair.

Who can do laser hair removal

All healthy people, who do not have any chronic illness, and who are over 18 years old can have laser hair removal.

Currently, different types of laser devices allow sessions to be performed on all skin types, even black skin, in which cases the 800 nm diode laser and the 1,064 nm Nd:YAG laser are recommended. Find out ARTICLE NOT FOUND IN EN: more about hair removal on black skin.

On fair and light brown skin, the Alexandrite laser is the most effective, followed by the dioso, Nd:YAG and Ruby lasers.

Contraindications for laser hair removal

Contraindications for laser hair removal include:

  • Very light or white hair;
  • Uncontrolled diabetes or high blood pressure;
  • Labial or genital herpes;
  • Epilepsy;
  • Pregnancy;
  • Use of photosensitizing medications, such as isotretinoin, in the previous 6 months;
  • Skin diseases, such as psoriasis or vitiligo;
  • Open wounds or recent hematoma at the site of laser exposure;
  • People undergoing cancer treatment.

Laser hair removal can be performed on almost all areas of the body with the exception of the mucous membranes, the lower part of the eyebrows and directly on the genitals.

It is important that laser hair removal is carried out by a dermatologist or a professional specialized in cosmetics and in a suitable environment. If the intensity of the device is not well set, there may be burns, scars or changes in skin color (light or dark) of the treated region.