Sun damage to your skin collects from the day you are born.  At its worst, sun damage can result in skin cancer that requires surgery.  For most people, sun damage is reflected in the fine lines, wrinkles, and spots that accumulate as you age.

Photo Dynamic Therapy or PDT is a treatment that specifically targets the sun damaged cells in your skin.  It uses a combination of a drug applied to your skin and a low intensity light system that activates the medication, killing sun damaged cells.  Depending on the degree of damage, several treatments are usually needed to achieve the best result.

How does it work?

There are three parts to your PDT treatment: Apply the medication, allow the medication to react with your skin, and allow your skin to react with the light source.

The medication:  The medication is called 5-ALA, or 5-alpha levulenic acid.  For skin cancers (or pre-cancerous conditions), a 20% concentration of the drug is used.  For less severe damage, lower concentrations are used.  For most patients, a mosaic of drug concentrations is used, treating the range of visible sun damage.  With higher drug doses, a more aggressive response is seen.  This more aggressive response will also mean more discomfort & redness during your healing.

Reaction Time:  Similar to adding yeast to bread dough, the longer the drug is allowed to react with your skin, the more damaged skin cells will be eliminated during treatment.  The more damaged cells removed during each treatment, the more redness and peeling is to be expected.  Treatment is tailored to balance the results of treatment and the nuisance of your recovery.  Reaction times may vary from 30 minutes to 18 hours.

Light Treatment:  Currently, there are two types of light used: Red & Blue.  Blue light is more reactive with the chemical, but does not penetrate as deeply into your skin.  Red light penetrates well into the deeper skin layers, plus it stimulates collagen.  Occasionally, both red & blue light treatments may be used during the same treatment session.

During light treatment, on a scale of 1-10, discomfort has ranged from 2-8.  Higher levels of discomfort correlate to the degree of sun damage, the drug concentration, and the reaction time for the drug with your skin.  Higher drug concentrations used for longer periods of time will expect to see more discomfort.  Typically, discomfort fades quickly after the light treatment is done.  Any lasting discomfort can be treated with small doses of medication.

After Treatment: Your skin will feel like a sun burn.  The degree of discomfort and redness can vary greatly. Although no one wants dramatic peeling or redness, a greater reaction to treatment also usually indicates a more dramatic result.  In general, we try to tailor your individual treatment to limit the redness, peeling, and flaking to just a couple days.

For the first day, cool compresses will help limit discomfort.  Topical sun burn care products, such as aloe, are also helpful.  If you experience discomfort that you expect will keep you awake at night, please call the office. 

Lubrication, such as Vaseline, Eucerin, or Aquaphor can be used as needed for comfort.  In rare instances, severe dryness (like “winter’s itch”) can lead to small areas of cracking and bleeding.  These areas should be treated with antibiotic ointment, such as Bacitracin.

Periodic photographs and complexion analysis will be done.  You should not be surprised if the number of sun damage spots should initially rise.  I believe this represents pre-existing sun damage that was not obvious.  Currently, I believe that when your measure for sun damage begins to drop, 1-2 additional PDT treatments are still needed.

Long Term:  Like spring cleaning at home, periodic maintenance treatments will be needed.  The time between maintenance PDT care will depend on your skin type, the degree of sun protection you use, and the amount of sun exposure you receive.

Based on the history of PDT as a treatment for skin cancer, I believe that long term treatment limiting sun damage will be shown to reduce long term risk of skin cancer.  Although this is my personal belief, there is not yet any hard data to support this conclusion.