This varies from one candidate to another. To achieve optimal reduction in undesirable hair growth, a series of laser treatments is needed in intervals. A gap in between the treatments is necessary so that every targeted hair follicle actively grows hair and so the laser can work to thermally destroy them. Typically, dermatologists recommend 4-8 laser hair removal sessions spaced 4 to 6 weeks apart. Your dermatologist will tell you when it is the right time to safely undergo another laser session for unwanted hair removal.