Photodynamic Therapy for Acne Vulgaris and Sebaceous Gland Hyperplasia

Photodynamic therapy (PDT) as a treatment for acne has been proven to be highly efficacious. The choice of the light source, photosensitizer type and dose, light source and dosimetry, incubation time and number of treatments and spacing makes protocols for PDT complicated. 5-Aminolevulinic acid, methyl aminolevulinic acid, methylene blue, indole acetic acid, and indocyanine green have all been used successfully as photosensitizing agents. Red light, pulsed dye lasers, intense pulsed light, and blue light have also been employed with good results. Complications can include discomfort, scaling, and sterile pustulation. Pain during procedures is not an issue for pulsed light devices; reducing the energy used for red light from that used for eradication of actinic keratosis mitigates the side effects. The mechanism of action is thought to include apoptosis of sebaceous glands (SGs), immune modulation, reduction in sebum secretion, and bactericidal effects. Although limited studies exist, PDT for treatment of SG hyperplasia has also been found to be effective. Calls for reduction in antibiotic use by the Centers for Disease Control, the President of the United States, and the thought leaders in acne mean that PDT should become a more commonly used treatment for acne. Limitations to its use include lack of commercial insurance coverage, need for avoidance of light for 48 h, and side effects. Enhancements to PDT may include heating and/or microdermabrasion prior to treatment. PDT continues to be one of the most effective treatments for inflammatory acne.