Photodynamic Therapy- Known by several names, "PDT" or "BLU-U" treatment offers effective, non-invasive and pain-free blue light treatment for moderate inflammatory acne, a condition affecting millions of adults, teens and children in the United States. The special wavelength blue light kills acne bacteria within the skin, with little downtime. PDT or BLU-U can be combined with a drug called Levulan for the longer term acne treatment, as well as treating photo-aging and certain non-cancerous lesion of the face and scalp. A series of 1-3 treatments are recommended for optimal results. Areas that can be treated include the face, scalp, back, chest and hands.