Photobiomodulation for the Management of Alopecia: Mechanisms of Action, Patient Selection and Perspectives

Photobiomodulation (PBM), also known as low-level laser therapy, was explored as a treatment for alopecia, with its origins tracing back over 50 years to observations of hair regrowth in mice exposed to a ruby laser. The review discussed the application of PBM in managing three main types of alopecia: androgenetic, areata, and chemotherapy-induced. It detailed the mechanisms by which PBM could promote hair regrowth, the types of devices used (primarily low-powered red laser diodes), and the dosimetry involved. The review also summarized findings from animal models and clinical trials, and provided criteria for selecting suitable patients for PBM therapy. The perspectives section anticipated future developments in the field.