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What is Photodynamic Therapy (PDT)?

Photodynamic Therapy is the delivery of very specific wavelengths of light to targeted tissues in the skin in conjunction with the application of aminolevulinic acid to provide the optimal correction of skin conditions.

Photodynamic Therapy is used to treat a number of skin conditions, including:

How is Photodynamic Therapy (PDT) Performed

Photodynamic treatments are performed at intervals of four to six weeks.  The number of treatments, the treatment time, and the treatment intervals will depend on the condition being treated and its extent.

The first stage in Photodynamic Therapy is the application of aminolevulinic acid, which is then allowed to absorb into the skin for 1-3 hours. The aminolevulinic acid is a photosensitizer, a compound that makes certain tissues in the skin, such as tumorous tissues and other abnormal skin cells, more susceptible to absorption of light at the specific wavelengths used during the therapy.

After the aminolevulinic acid is sufficiently absorbed, a topical anesthetic is applied to reduce discomfort, and then the light is applied. The light appears blue, and it selectively targets tissues that absorbed the aminolevulinic acid. Although it is reduced by the topical anesthetic, most patients feel a mild burning or itching sensation that may last from one hour to two days following treatment.

You may also experience redness and swelling for 1-3 days after treatment. Ice and cold packs can help bring the swelling down. Strict sun avoidance is necessary for 48 hours following treatment as the skin may be sensitive to light, especially sunlight because of remaining aminolevulinic acid in the skin. Use sunscreen and a hat to diminish the resulting discomfort. You may also experience some mild peeling of the skin. Gentle emollients should be applied to the skin.

Why Photodynamic Therapy (PDT)?

In contrast to other therapies for these skin conditions, PDT has a number of advantages, including:

If you are interested in learning more about PDT, schedule a Photodynamic Therapy consultation with one of our doctors at the Dermatology & Laser Surgery Center.