It is done in five to ten sessions at two to six week intervals. Brightening shows from the third, because it breaks pigment into fine fragments rather than shattering it hard in one pass, so sessions are needed. Clearing the fragments also takes the body that long.

Ordinary toning breaks pigment with heat; pico toning delivers only a shock in an extremely brief pulse, so thermal damage is low. There is no time for heat to spread, so surrounding skin is less irritated. That lowers the risk of irritation producing more pigment, which suits sensitive pigment such as melasma.

Melasma can return under the influence of UV and hormones, because breaking the pigment down does not remove the cause that makes it. The basic approach is to lighten it with treatment and then maintain with sun protection and topical medication, with extra care in summer.