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.
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 the eyelid or surrounding area.
Hair color 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 color — dark hair and light skin — results in the best outcomes.
The risk of damage to skin is greater when there is little contrast between hair and skin color, 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 colors that don't absorb light well: gray, red, blond and white. However, laser treatment options for light-colored hair continue to be developed.
Risks of side effects vary with skin type, hair color, treatment plan and adherence to pre-treatment and post-treatment care. The most common side effects of laser hair removal include:
- Skin irritation. Temporary discomfort, redness and swelling are possible after laser hair removal. Any signs and symptoms typically disappear within several hours.
- Pigment changes. Laser hair removal might darken or lighten the affected skin, usually temporarily. Skin lightening primarily affects those who don't avoid sun exposure before or after treatment and those who have darker skin.
Rarely, laser hair removal can cause blistering, crusting, scarring or other changes in skin texture. Other rare side effects include graying of treated hair or excessive hair growth around treated areas, particularly on darker skin.
Laser hair removal isn't recommended for eyelids, eyebrows or surrounding areas, due to the possibility of severe eye injury.
How you prepare
If you're interested in laser hair removal, choose a doctor who's board certified in a specialty such as dermatology or cosmetic surgery and has experience with laser hair removal. If a physician assistant or licensed nurse will do the procedure, make sure a doctor supervises and is available on-site during the treatments. Be cautious about spas, salons or other facilities that allow nonmedical personnel to do laser hair removal.
Before laser hair removal, schedule a consultation with the doctor to determine if this is an appropriate treatment option for you. Your doctor will likely do the following:
- Review your medical history, including medication use, history of skin disorders or scarring, and past hair removal procedures
- Discuss risks, benefits and expectations, including what laser hair removal can and can't do for you
- Take photos to be used for before-and-after assessments and long-term reviews
At the consultation, discuss a treatment plan and related costs. Laser hair removal is usually an out-of-pocket expense.
The doctor also will offer specific instructions to prepare for laser hair removal. These might include:
- Staying out of the sun. Follow your doctor's advice for avoiding sun exposure, usually up to six weeks before treatment, and use a broad-spectrum sunscreen daily.
- Lightening your skin. Avoid any sunless skin creams that darken your skin. Your doctor also might prescribe a skin bleaching cream if you have a recent tan or darker skin.
- Avoiding other hair removal methods. Plucking, waxing and electrolysis can disturb the hair follicle and should be avoided at least four weeks before treatment.
- Avoiding blood-thinning medications. Ask your doctor about what medications, such as aspirin or anti-inflammatory drugs, to avoid before the procedure.
- Shaving treatment area. Trimming and shaving is recommended the day before laser treatment. It removes hair above the skin that can result in surface skin damage from burnt hairs, but it leaves the hair shaft intact below the surface.
What you can expect
Laser hair removal usually requires a series of two to six treatments. The interval between treatments will vary depending on the location. On areas where hair grows quickly, such as the upper lip, the treatment might be repeated in four to eight weeks. On areas of slow hair growth, such as the back, the treatment might be every 12 to 16 weeks.
For each treatment you'll wear special goggles to protect your eyes from the laser beam. An assistant might shave the site again if necessary. The doctor might apply a topical anesthetic to your skin to reduce any discomfort during treatment.
During the procedure
The doctor will press a hand-held laser instrument to your skin. Depending on the type of laser, a cooling device on the tip of the instrument or a cool gel might be used to protect your skin and lessen the risk of side effects.
When the doctor activates the laser, the laser beam will pass through your skin to the hair follicles. The intense heat from the laser beam damages the hair follicles, which inhibits hair growth. You might feel discomfort, such as a warm pinprick, and you'll likely feel a sensation of cold from the cooling device or gel.
Treating a small area, such as the upper lip, might take only a few minutes. Treating a larger area, such as the back, might take more than an hour.
After the procedure
You might notice redness and swelling for the first few hours after laser hair removal.
To reduce any discomfort, apply ice to the treated area. If you have a skin reaction immediately after laser hair removal, the doctor might apply a steroid cream to the affected area.
After laser hair removal and between scheduled treatments, avoid sun exposure — both natural sunlight and tanning beds — for six weeks or as directed by your doctor. Use a broad-spectrum sunscreen daily.
Hairs do not fall out immediately, but you will shed them over a period of days to weeks. This may look like continued hair growth. The repeated treatments are usually necessary because hair growth and loss naturally occur in a cycle, and laser treatment works best with hair follicles in the new-growth stage.
Results vary significantly and are difficult to predict. Most people experience hair removal that lasts several months, and it might last for years, but laser hair removal doesn't guarantee permanent hair removal. When hair regrows, it's usually finer and lighter in color.
You might need maintenance laser treatments for long-term hair reduction.
What about home lasers?
In recent years, lasers that can be used at home for hair removal have become available. These devices might cause modest hair reduction. But there are no large studies comparing how effective these devices are compared with laser hair removal done at a doctor's office.
Additionally, the Food and Drug Administration considers these home laser hair removal devices to be cosmetic, not medical, which means they don't get the same level of scrutiny as other medical devices. Currently, there haven't been large, long-term studies on how safe and effective the home machines are.
If you choose to use a home laser hair removal device, follow the instructions that come with the device to help reduce the risk of injury, especially eye injuries.