Small area, quick sessions — often the first area people choose.
Laser energy is absorbed by the dark pigment in the hair and at its root, turning into heat that damages the structure driving growth. It only works on hair that is growing now, so sessions repeat in step with the hair cycle. The area is small, so a session finishes quickly.
It takes about six to eight sessions at four to eight week intervals. The laser only responds to hairs currently growing, and hairs grow on different cycles, so not all are caught in one pass. Underarm hair is coarse and dark, so the laser is absorbed well and change is clear from the third to fifth session.