Effects of Blue Light on the Skin and Its Therapeutic Uses: Photodynamic Therapy and Beyond

BACKGROUND: Blue light is the most energetic portion of the visible light spectrum. Recent awareness of its ubiquity and potential has led to greater developments in therapeutic uses. OBJECTIVE: Provide up-to-date information on the effects of blue light on the skin, with a focus on the benefits and its place in therapeutic modalities within dermatology. MATERIALS AND METHODS: A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for articles related to blue light's effect on the skin and therapeutic modalities using blue light. This search resulted in 223 unique results with 60 articles selected for review. RESULTS: Therapeutic modalities using blue light have been proven to be effective as a monotherapy or component of a comprehensive treatment plan for common dermatologic diseases such as actinic keratosis, acne, cutaneous infections, and psoriasis, and early reports support its use in disseminated superficial actinic porokeratosis and actinic cheilitis. CONCLUSION: The benefits and treatment applications of blue light have proven effective in multiple forms and uses. In the correct setting, blue light can be a useful tool to the practicing dermatologist for many common and sometimes refractory skin diseases while remaining low-risk and convenient. Further standardization and monitoring should be pursued to determine the most appropriate use.