The Use of Light-Based Therapies in the Treatment of Alopecia.

BACKGROUND: Alopecia encompasses a group of conditions that can significantly impact quality of life, especially among women and younger individuals. While pharmaceutical therapies remain the cornerstone of treatment, laser and light-based therapies, especially low-level light therapy (LLLT), offer promising noninvasive alternatives. LLLT uses specific wavelengths of light to stimulate hair follicle repair, prolong the hair growth phase, and promote regrowth. Recent advancements in at-home devices and dual-wavelength LED systems have expanded access to these therapies. This review explores the role of LLLT in treating alopecias, evaluating its mechanisms, efficacy, and clinical applications. METHODS: A PubMed search using terms related to alopecia and laser/light therapy was conducted. Results were limited to English-only articles from 2020 to 2025, excluding duplicates. Additional articles were identified through citation tracking. Studies not focused on light-based therapies were excluded. RESULTS: Of 403 articles identified, 63 were included based on relevance to alopecia or hair loss and light-based therapy. Results were categorized by treatment modality and type of hair loss, with overlap between categories. DISCUSSION: This review highlights the growing role of LLLT as an adjunct or alternative treatment for various types of alopecia. In androgenetic alopecia, LLLT improves hair density and follicular responsiveness, with enhanced outcomes when combined with minoxidil or finasteride. For telogen effluvium, LLLT shows potential in prolonging the anagen phase and reducing shedding, although larger studies are needed. In alopecia areata, LLLT may promote regrowth by modulating immune responses and improving perifollicular microcirculation. Emerging data also support LLLT in lichen planopilaris and central centrifugal alopecia (CCCA), with case reports showing reduced inflammation and hair regrowth. Overall, LLLT offers a noninvasive, well-tolerated option across alopecia subtypes, though standardized protocols and long-term data remain limited.