Photodynamic therapy (PDT) is a procedure that uses a photosensitizing drug to apply light therapy selectively to target pre-skin cancer, acne and sun damage.
WHAT IT TREATS
PDT can help clear the skin of actinic keratoses which are premalignant growths in sun-exposed areas, mainly the face, chest, arms, and hands. It is also effective for moderate to severe acne. A series of treatments can put acne into remission for months as well as reverse some scarring without the need for oral medications. There are many less common conditions that PDT can be used for, including hidradenitis suppurativa, Bowen’s disease, superficial basal cell carcinoma, and others.
WHAT TO EXPECT BEFORE, DURING, AND AFTER THE PROCEDURE
The skin will be cleansed thoroughly; practitioners will perform an acetone scrub immediately before application of the drug to increase penetration. The aminolevulinic acid, a clear liquid, will be applied to the entire surface of the skin that is to be treated. This will incubate, or be absorbed, for 30 minutes to 3 hours, depending on your condition. You will feel some burning discomfort during the treatment. You will be provided a fan which helps to reduce the burning sensation. After the treatment the skin involved will be extremely light sensitive for 48 hours until the medication is completely metabolized. Hats, scarves, and thick sun block with zinc oxide and light avoidance are required to protect the skin during that time. Most of the time, some redness and mild peeling will occur over the first two to three days. Occasionally, there can be discomfort for 24 hours and more prolonged peeling and redness for 5 to 14 days.
COMPLICATIONS THAT CAN OCCUR
Although not a “complication,” the “PDT effect” is the most common problem associated with this procedure. “PDT effect” is the redness and peeling that occurs after the procedure. This can be pronounced with significant crusting and some discomfort. Severe reactions occur usually for one of two reasons. If someone has a large number of pre-skin cancers, much more of the drug will be absorbed and there will be a stronger reaction. People sometimes think that driving in their car is “staying inside” or running a few errands is okay, but the sun’s rays penetrate through window glass and even high SPF sun block is not adequate protection during the first 48 hours. However, following therapy the PDT effect resolves within one to two weeks. People who have severe reactions often have excellent results.
Typically, we recommend two treatments separated by about one month. Generally, the second treatment is much easier to tolerate than the first treatment.