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Photodynamic Therapy

Photodynamic therapy is being recommended to treat pre-cancerous lesions (actinic keratosis) on your skin. These precancerous lesions can have several causes; UV radiation, genetics, exposure to such cancer-causing substances (carcinogens) as smoking (including “side smoke”), arsenic, tar or x-ray radiation.

What is Photodynamic Therapy?

Photodynamic therapy or PDT is a treatment that uses special drugs, called photosensitizing agents, along with light to kill precancerous and cancer cells. The drugs only activate only after they have been “turned on” by exposure to certain wavelengths of light. The photosensitizing agent is applied in the office to the skin and binds to pre-cancerous or cancerous cells over 45-60 minutes. Then, light to activate this topical agent causes the drug to react with oxygen, which forms a chemical that kills the precancerous or cancerous cells. The drug that is applied to treat precancerous cells (Actinic Keratosis) is ALA (aminolevulinic acid HCI) topical solution. The solution is absorbed by the actinic keratosis cells and then converted to a chemical that makes these cells extremely sensitive to certain wavelengths of light. When the actinic keratosis cells are exposed to the blue light illuminator, a reaction occurs in which the actinic keratosis cells are destroyed.

Preparing for Treatment

Before the photodynamic treatment, be sure to tell your healthcare provider if you are taking ANY oral medications or using topical prescriptions, or non-prescription products on the area that the provider will be treated. Bring adequate sun-protective ítems to your visit (examples: wide brimmed hats (garden hats), umbrella, sun-protective clothing) for the area that is to be treated. You must wear a physical sunscreen if the area that is being treated will not be covered completely from any light for the next 48 hours. If you cannot find an adequate chemical-free, physical sunscreen of a high enough quality for this purpose, we will provide you with one. After the treatment is over with, we will apply one of these 2 physical sunscreens and make sure you are protected from sunlight before you leave the office.

Avoid exposure to sunlight or indoor ultraviolet or blue light (ex: refrigerator section for milk) for at least 40 hours after the treatment. Reapply the physical sunscreen every 2 hours. We highly recommend that you stay indoors. We will call your insurance to see if it is covered. If the procedure is covered, if it will be applied to a deductible if applicable, and if applicable you may have a co-pay. Please contact us if you have any questions.


Since diagnosis is the first step to managing any skin condition, those who suffer from pre-cancerous lesions such as actinic keratosis, should request a consultation appointment: call Dermatology Specialists of Atlanta at 678-904-4932 now.

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