Chapter 21 - Photodynamic Therapy for Acne, Rejuvenation, and Hair Removal

Abstract

Publisher Summary This chapter discusses the photodynamic therapy for acne, rejuvenation, and hair removal. Photodynamic therapy (PDT) is a century-old treatment for neoplastic conditions, which most recently has evolved to treat acne and photoaging. PDT is often used for therapeutic challenges. Basic science studies indicate that topical ALA results in preferential accumulation of PpIX in hair follicles, with highest expression during the anagen phase. This makes actively growing hair susceptible to light-mediated destruction, as shown in rodent models. Clinical studies are needed in order to determine whether this would be a viable mode of hair removal, provided the protocol is optimized to maintain the efficacy of hair follicle destruction without the risk of significant side effects and complications. There was only one published clinical study regarding the use of PDT for hair disorders in humans aimed at treating the hair-loss disease alopecia areata with topical ALA followed by red light. PDT has been used to treat cutaneous neoplasia, and recently this application has been extended to include photoaging, the cutaneous manifestation of sun-induced aging to the skin. The current protocols in use involve the topical application of ALA for short incubation followed by blue light, LP PDL, or IPL. Among these light sources, IPL is the best studied and most obvious choice, since it has well-demonstrated efficacy in photorejuvenation, which is augmented with antecedent ALA application.