Photodynamic Therapy (PDT) for Acne


This non-invasive outpatient procedure uses a topical, light-activated medication to reduce or eliminate acne. It can improve the appearance of acne scars.


To prepare for the procedure, the physician cleans the skin to remove as much oil as possible. The physician may use a dermabrasion tool to remove dead cells from the skin's outer layer. A topical medication called aminolevulinic acid (or ALA) is then applied to the skin and left on for up to an hour. The ALA is absorbed by the skin, especially by the skin's oil glands. This is where the bacteria that cause acne reside.

Light Treatment

Once the absorption is complete, the medication is activated with a specific wavelength of light. The skin is exposed to a blue light source for several minutes. The ALA reacts to the light, killing the acne bacteria and causing the oil glands to become less active. The treatment also helps rejuvenate the skin, softening the appearance of acne scars.


Following the treatment, the patient will experience redness, tenderness and peeling of the treated area. The treated skin must be protected from sunlight for 24 to 48 hours after the procedure. The skin will completely heal within a few weeks. Multiple treatments, performed a few weeks apart, may be required to achieve optimal results.