The presence of unwanted hair continues to plague many individuals for whom traditional methods of hair removal remain unsatisfactory. Old methods of removing unwanted hair include shaving, waxing, chemical depilation, and electrolysis, all of which have temporary results. The invention of photothermolysis and the development of various laser systems with many ranges of wavelengths have made effective hair removal possible.
There has been an explosive increase in the use of lasers for hair removal since the first lasers were approved in 1996. Since then, numerous advances in laser hair removal, which use melanin as a chromophore, have been made. Laser hair removal is commonly used to remove unwanted hair on the face, neck, armpits, chest, back, genital area, arms, legs, fingers, toes and feet.
How does it work?
Laser hair removal is accomplished through follicular unit destruction. The ability to remove hair without damaging the surrounding skin is based on selective photothermolysis—the theory that at a particular wavelength, pulse duration, and fluence, thermal injury is confined to a target that contains a light-absorbing molecule called a chromophore.
Laser-assisted hair removal is the most efficient method of long-term hair removal currently available. Several hair removal systems have been shown to be effective in this setting: the ruby laser (694 nm), the alexandrite laser (755 nm), the diode laser (800 nm), an intense pulsed light source (590 to 1200 nm), and the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (1064 nm), with or without the application of carbon suspension. Both the long-pulsed alexandrite and the long-pulsed diode laser systems are effective in the treatment of unwanted hair, and they are more effective than the Nd:YAG laser. The parameters used with each laser system vary considerably.
After the treatment, redness and swelling may persist for the first few hours. If skin reaction appears immediately after laser hair removal, steroid cream can be applied to the affected area. Hairs do not fall out immediately, but will be shed 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. Maintenance laser treatments are usually recommended for long-term hair reduction.
Complications of laser treatment for hair removal
The most common complications 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.