Photodynamic therapy or blue light therapy is an FDA approved treatment for actinic keratoses. Actinic keratoses are pre-cancerous lesions that have a chance of transforming into squamous cell carcinoma. Prior to the procedure, aminolevulinic acid is placed on the skin that will be treated. The area is then exposed to blue light that activates the medication and destroys the pre-cancerous lesions. There are several treatments for actinic keratoses, and your Dermatologist will recommend the best treatment for you. The benefit of photodynamic therapy is that several pre-cancerous lesions can be treated at the same time.