Blue light photodynamic therapy (pdt) has been used for over a decade for the treatment of actinic keratosis, acne, and some superficial skin cancers, but has been associated with moderate discomfort during treatment. A new protocol using 2 and a half hours of natural sunlight instead of 16 minutes of blue light has been studied with promising results equaling the efficacy of blue light. Patients can now get the benefits of pdt without the discomfort.
Patients come into the office to have the medication applied. They go hone and sit in the shade for 150 minutes. They must avoid the sun for two days, which is the same restrictions as blue light pdt.