Photodynamic Therapy (“Blue U”): A Great Treatment Option for Sun Damage and Pre-Cancer

by Joel Bain Herron, MD

We’ve long known that sun exposure, over time, can be damaging to the skin. But until recently, we haven’t had many choices about how to treat sun damage.

Photodynamic therapy has become one of our preferred methods to treat areas of sun damage or pre-cancer. Photodynamic therapy, also known as the “blue U” or “blue-light treatment,” involves the application of a photosensitizing topical medication (aminolevulinic acid) that is then activated by a light source. The medication is absorbed by sun-damaged and pre-cancerous cells and is also taken up by the oil glands in the skin. After the medication has had time to absorb, the patient sits in front of or beneath a blue light source for 1,000 seconds (16 minutes 40 seconds). The light itself is in the shape of a “U,” which is why it is often called “the blue U.”

Once activated by the light, the aminolevulinic acid goes through a series of chemical reactions and produces oxygen radicals that are toxic to the unwanted cells. Thanks to this specificity, photodynamic therapy allows us to selectively target the pre-cancerous and sun-damaged cells while mainly leaving the normal cells unaffected.

Proactive skin cancer prevention

This therapy can be used preventatively and proactively instead of waiting until problems arise to address them, and it may even be used successfully in the very early treatment of some skin cancers. One of the biggest advantages is treating entire areas such as the face, hands, arms, legs, and chest. With previous treatments like liquid nitrogen, we’re only able to treat specific spots, one at a time.

There’s an additional benefit to treating sun damage with photodynamic therapy. Many patients will experience a subtle rejuvenation of their skin, with an improvement in appearance and texture. Some also notice a reduction of liver spots or lentigos. Because the medication is taken up by oil glands, photodynamic therapy can also be used to treat acne and reduce overgrown oil glands.

Because aminolevulinic acid is activated by light, the area that was treated will be sensitive to bright light or sunlight for approximately two days after the procedure. It is of the utmost importance that patients keep treated areas protected with either sunscreen or protective clothing. Generally, patients leave our office slathered in sunscreen or wearing a hat after this procedure. We recommend both!

Is there any downtime?

The longer the medication is left on the skin to incubate, the more medication is taken up by cells, and subsequently, a more vigorous response is produced. When photodynamic therapy was first introduced, the protocol was to leave the medication on overnight before treatment, which we have since determined is an unnecessarily long amount of time. As a result, an internet search will reveal patients warning others that this therapy is very uncomfortable and results in a lot of redness. Fortunately, we have new and improved medications and protocols that allow for very tolerable and mild side effects while still maintaining a high efficacy level. In fact, most patients say they feel like they spent a bit of time in the sun, and some experience a touch of pinkness for a day or two.

Does insurance cover photodynamic therapy?

Because this treatment is FDA approved for the treatment of pre-cancerous lesions, it is usually a covered benefit through insurance. Treatment of acne, overgrown oil glands, or use for purposes of rejuvenation is usually considered cosmetic in nature. Please feel free to schedule an appointment with one of our providers in order to learn more about this treatment and see if it is right for you.