New Jersey State Board Esthetics Practice Exam

At what stage of hair growth is laser hair removal most effective?

1. Telogen

2. Anagen

3. Catagen

4. Interphase

The correct answer is: Anagen

Laser hair removal is most effective during the anagen phase of hair growth, which is the active growth phase. During this stage, hair follicles are fully developed and actively producing hair, making them more susceptible to the laser's energy. The laser targets the pigment in the hair, and since the hair is growing and contains the most melanin during anagen, the treatment can effectively damage the hair follicle to reduce future hair growth. In contrast, during the telogen phase, hair is in the resting stage and not actively growing, making it less responsive to laser treatment. The catagen phase is a transitional stage when hair growth has slowed down and follicles are beginning to shrink, further diminishing the effectiveness of laser hair removal. Interphase is not a recognized stage in the hair growth cycle, which adds to the distinction of why the anagen phase is specifically the target for successful laser hair removal treatments.