The "blue" light used for this modality is narrow-bands of blue rays in the visible light spectrum of 415-420 nanometers. The light is very safe but requires the patient to use safety goggles throughout the standard 15-20 minute treatment. There is concern that prolonged exposure to the light without eye protection may result in eye irritation and/or cataracts. Wearing the proper goggles will prevent this. There is no sensation or even heat associated with the light therapy. The biggest complaint we receive is that it is boring. We often caution our acne patients to not undervalue the Blu-U treatments which is often the case when there is no sensation associated with treatments.
How does Blue Light Therapy Work?
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Blue Light Therapy and Photodynamic Therapy (PDT) for Acne
BLU-U technology uses high-intensity, 405-420nm wavelength light. This is outside of the cancer-causing ultraviolet UV spectrum between 290-400nm. Intense pulse light laser (IPL) or photofacial utilizes 560-1200nm depending on which filter is used dictated by different skin types. Unfortunately, the clinical efficacy of blue light therapy as a stand alone therapy for acne is quite modest requiring 1-2x/week for several weeks. What has been shown to be more efficacious is blue light preceded by aminolevulinic acid (Levulan) where the colonies of bacteria responsible for acne can be significantly reduced and the secretion from oil glands can be minimized. This is known as photodynamic therapy (PDT) and should be supervised by an experienced board-certified dermatologist who can customize specific incubation time (duration of Levulan left on the skin) as well as the exposure time (amount of time spent in front of a blue light source). Effective PDT treatment regimen typically requires 4 treatments, 2-4 weeks apart. PDT will work even better as an adjunctive therapy to the conventional oral and topical therapy prescribed by your board-certified dermatologist.