Home > Medical Dermatology > Photodynamic Therapy (PDT)

Photodynamic therapy (PDT) is a three-step treatment for mild or serious skin conditions. A photosensitizing drug is applied to the treatment area and a light source activates the chemical reaction. The resulting oxidation kills any cells that have absorbed the drug with few, if any, long-term side effects to the treatment area. PDT treatment is most commonly used to remove abnormal cells that cause actinic keratosis, a pre-cancerous condition, as well as other precancerous skin growths.

What to Expect During PDT Treatment

At the beginning of the procedure, Levulan, a topical photo sensitizer, is applied to the skin and left for an incubation period of several minutes to several days. Levulan is essentially aminolevulinic acid (ALA), which is a natural substance that’s already in the body.
After incubation, Levulan is activated through exposure to a specific wavelength of light. Patients may experience sensations of warmth, tingling, heat or burning during this part of the photodynamic therapy.
The treated area is then washed, and patients may return home. Most people return to work within one to two days of the procedure. Rarely, patients may experience complicated during healing but these usually last only a week or a week and a half at most.

Patients may need as many as five PDT sessions for optimal results. This is more common with severe skin conditions and more aggressive treatment plans. Sessions are spaced two to five weeks apart and can be continued afterwards to help maintain the initial results of the treatment.

What are the Side Effects of Photodynamic Therapy?

PDT is a generally safe treatment procedure, but there are certain risks and side effects associated with this minimally invasive procedure. Some of these risks and side effects include redness, bruising, discoloration, and infection. These side effects are usually mild and usually go away within a few weeks. Scarring is also very minimal or even negligible, especially if infection is avoided following the procedure.

What is Photodynamic Therapy Used For?

In addition to pre-cancerous skin growths, PDT treatment may be used for some types of skin cancer and other growths within 1/3 inch of the skin. The activating light cannot reach any deeper. Thus, tumors that are large, deep, or aggressive are not usually a good candidate for PDT treatment. New clinical trials continue to explore the potential benefit of PDT procedures.

While it is widely used for skin growths, PDT is also sometimes used as an experimental treatment for other types of cancer in which the tumor resides close to the surface of the skin. It may also be used for palliative care to shrink neck and throat tumors that are interfering with the person’s ability to breathe or swallow.

Talk to a Dermatologist about PDT Treatment

The most common PDT treatment is used for actinic keratosis, but there are several other skin conditions that may be a candidate for this procedure. Laser treatment is another type of treatment method that is available for multiple skin conditions. Sit down with a certified dermatologist to come up with the best treatment approach for your skin condition.

*Results may vary per patient.