Photodynamic therapy (PDT) is an effective skin treatment
for sun damage, acne, and pre-skin cancer growths called actinic keratosis on
the face, chest, arms, and hands. PDT uses a topical acid and light treatment
to target damaged areas of skin and oil glands without affecting healthy skin.
How photodynamic therapy is performed
Photodynamic therapy is a non-invasive in-office treatment
that can take 1-4 hours depending on your skin care needs.
Your dermatologist will begin by cleansing your skin and marking
out the treatment area with a pen. Then aminolevulinic acid (ALA), which is a
clear liquid, is applied to your skin and allowed to soak in for 30 minutes to
3 hours depending on your skin condition and the type of light that will be
used. The ALA makes damaged skin cells and acne-causing oil glands extremely
sensitive to light exposure. A topical numbing cream may also be applied for
After the ALA has soaked in, your skin is then cleaned and your
dermatologist shines a blue or red light onto your skin for about 15 minutes. These
special lights target and destroy areas of sun damaged skin, pre-cancerous
cells, and acne causing oil glands without damaging healthy skin. You may feel a
mild stinging or burning sensation during the light treatment.
Recovery and results
Photodynamic therapy can cause noticeable redness,
irritation, and skin peeling for about 10 days after treatment, similar to a sunburn.
You should be fully healed after about two weeks. You’ll have to avoid sun
exposure and wear strong sunblock 48 hours after treatment because your skin
will still be hyper-sensitive to light. Some people may need multiple
treatments spaced two to four weeks apart for best results.