Laser is the only clinically-proven way to remove a tattoo without causing scarring to your skin. Many tattoo inks are made of heavy metal compounds, such as manganese, copper, and lead. These metal compounds make a tattoo permanent.
The ink in your tattoo is targeted with pulses of highly concentrated light, and this light breaks down the ink into tiny fragments that those white blood cells can pick up and carry away for removal.
However, covering up unwanted tattoos with a new tattoo increases the difficulty of removal. Multiple sessions are required if more tattoo colours are being used.