Photodynamic Therapy (PDT) is completed in a 2-stage process. Stage 1 includes topical application of a photosynthesizing agent that makes the skin extremely sensitive to light. Stage 2, which takes place 14 to 18 hours after the medicine is applied and includes a 20 minute session exposing the area being treated to a BLU-U Blue Light. After stage 1 - avoid exposure to sunlight or bright indoor light.
After the procedure is complete, protect treated area from the sun by wearing a wide-brimmed hat or head covering. Sunscreen will not help protect against a photosensitive reaction. Side effects may include redness, swelling, and crusting which may last up to 4 weeks. You may begin reapplying makeup after crusting resolves.