Photodynamic Therapy for the Treatment of Actinic Keratosis

Photodynamic therapy (PDT) is a safe, effective treatment for actinic keratosis, precancerous lesions caused by sun damage.

How Photodynamic Therapy Works

In photodynamic therapy, a photosensitizing agent is applied to the skin followed by exposure to an intense light source, which activates the agent and destroys the now light-sensitive lesions. In some cases, pretreatment or scraping of the lesion is required to improve penetration prior to the application of the photosensitizing solution.

Once the agent has been applied, your dermatologist may use a light source to activate it. The most widely used light source is a blue light, but red light devices have also been approved for use in photodynamic therapy.

Is Photodynamic Therapy Right for You?

Since no single treatment is right for every patient, your dermatologist will discuss actinic keratosis treatment options and recommend the one that is right for you. Here are some advantages and disadvantages of photodynamic therapy.

Advantages of Photodynamic Therapy:

Photodynamic therapy can be administered in a single dermatology clinic appointment
Eliminates the risk of non-compliance that can occur with in-home treatments
Can be used in conjunction with other actinic keratosis treatments
Causes virtually no damage to surrounding skin
May be used to treat multiple actinic keratoses at once in one area

What to Expect from Photodynamic Therapy:

Usually requires 60-90 minutes incubation time for the photosensitizing agent, followed with a 16 minute treatment time with an activating light source.
Works best on shallow lesions on the face or scalp. Thicker lesions may require combination treatment.
Patients must avoid UV light exposure to the treated area for 48 hours after treatment.
A second treatment may be required in 2-4 weeks for optimal results.
Redness or swelling may occur after treatment.
PDT is not appropriate for patients taking medications that could increase photosensitivity.