While tattoos are considered permanent, it is possible to remove them. Complete removal, however, may not be possible (although many doctors and laser practitioners make the claim that upwards of 95% removal is possible with the newest lasers, especially with black and darker colored inks), and the expense and pain of removing them typically will be greater than the expense and pain of applying them. Some jurisdictions will pay for the voluntary removal of gang tattoos. Pre-laser tattoo removal methods include dermabrasion, salabrasion (scrubbing the skin with salt), cryosurgery, and excision which is sometimes still used along with skin grafts for larger tattoos.
Tattoo removal is most commonly performed using lasers that react with the ink in the tattoo, and break it down. The broken-down ink is then absorbed by the body, mimicking the natural fading that time or sun exposure would create. All Tattoo pigments have specific light absorbance spectrums. A tattoo laser must be capable of emitting adequate energy within the given absorbance spectrum of the pigment in order to provide an effective treatment. Certain tattoo pigments, such as yellows, greens and fluorescent inks are more challenging to treat than the darker blacks and blues. These pigments are more challenging to treat because they have absorbance spectrums that fall outside or on the edge of the emission spectrums available in the respective tattoo removal laser.
Laser tattoo removal often requires many repeated visits to remove even a small tattoo, and may result in permanent scarring. The newer Q-switched lasers are said by the National Institute of Health to result in scarring only rarely, however, and are usually used only after a topical anesthetic has been applied. The NIH recognizes five types of tattoo; amateur, professional, cosmetic, medical, and traumatic (or natural). Areas with thin skin will be more likely to scar than thicker-skinned areas. There are several types of Q-switched lasers, and each is effective at removing a different range of the color spectrum. These lasers effectively remove black, blue, purple and red tattoo pigment. New lasers like the Versapulse & Medlite laser treat these colors & yellow and green ink pigment, typically the hardest colors to remove. Black is the easiest color to remove. Both the Revlite and Medlite C6 lasers utilize specialized dye hand-pieces that transform the wavelength of energy emitted by the laser. This expansion of wavelengths gives the laser an enhanced ability to treat a much broader range of tattoo pigments than than standard Q-switched lasers.
Also worth considering is the fact that some of the pigments used (especially Yellow #7) are known to break down into toxic chemicals in the body when attacked by light. This is especially a concern if these tattoos are exposed to UV light or laser removal; the resulting degradation products end up migrating to the kidneys and liver. Laser removal of traumatic tattoos may similarly be complicated depending on the substance of the pigmenting material. In one reported instance, the use of a laser resulted in the ignition of embedded particles of firework debris.
Some wearers opt to cover an unwanted tattoo with a new tattoo. This is commonly known as a cover-up. An artfully done cover-up may render the old tattoo completely invisible, though this will depend largely on the size, style, colors and techniques used on the old tattoo. Some shops and artists use laser removal machines to break down and lighten undesired tattoos to make coverage with a new tattoo easier. Since tattoo ink is translucent, covering up a previous tattoo necessitates darker tones in the new tattoo to effectively hide the older, unwanted piece.