Photodynamic therapy: mechanism of action and role in the treatment of skin disease.

The combination of lesion ablation with excellence in cosmetic outcome has allowed photodynamic therapy (PDT) an ever increasing role in the treatment of diseases of the skin. As currently practiced, PDT employs a photosensitizing agent that when activated by light energy creates a photodynamic reaction that is cytotoxic and vasculotoxic. The relative simplicity of therapy with its ability to achieve high response rates has brought PDT to a worldwide audience not only for oncologic indications but far more commonly to non oncologic indications. This paper will review the mechanism of action for PDT and highlight the versatile clinical outcomes reported from the peer reviewed literature.