Photodynamic Therapy

Photodynamic Therapy (PDT)

Photodynamic therapy (PDT) is a combination treatment of light and a topical medication which together can help to treat a variety of skin diseases including actinic keratosis (pre-cancerous lesions), acne, photoaging, enlarged pores, and some skin cancers. Photodynamic therapy specifically treats the problem skin while leaving normal skin unaffected. Multiple lesions are simultaneously treated at each session and treatment may also prevent the development of new lesions.

In the first step, a topical medication is applied to the skin and is taken up by the targeted cells. The skin is then given time to absorb the medication and turn it into an active light sensitive form. Laser or light source exposure activates the light sensitive compound to decrease the number of targeted cells, such as cancerous, precancerous cells, oil glands or acne causing bacteria. Photodynamic treatments are safe, effective and well tolerated by most patients, but typically care must be taken to avoid exposure to sunlight for 48 hours following the treatment.

Frequently Asked Questions:

What is the process of the treatment?

PDT involves two steps. First, the photosensitizer is applied to clean skin. Depending on the area of treatment, the provider might do a gentle scraping of the precancerous lesions for greater absorption of the medication. Once the application is complete, the photosensitizer is left on the skin for the appropriate length of time, which may range from 1 to 3 hours.
Once the incubation time passes, the provider will then have you sit under a blue light for a short period of time. Under the specific light, the photosensitizing agent reacts with light, which in turn, reacts with oxygen to selectively destroys precancerous cells.

Is there any pain during the treatment?

During the treatment under the light, patients may experience burning, prickling, heating sensation. This is due to the occurrence of the reaction between the precancerous cells, the light, and photosensitizing agent.

What will I look like after the treatment?

Immediately post treatment, patients may appear to have sunburn like redness to the area treated. The skin may feel hot and tender, which can be alleviated by cool compresses. The effects are temporary and may include swelling, and scaling.

What is the typical healing time and expectations after treatment?

After you leave our office post treatment, it is very important that you avoid sunlight as it can cause further redness and burning. Sunscreen, although excellent for any other day, will not protect you against the photosensitivity. Although patient responses vary in duration and severity, the typical response can be as follows:

Days 1-2: You will be extremely sensitive to sunlight; patients are advised to avoid direct sunlight as it can cause pain and tenderness and stay indoors.

Day 3-4: The skin may scab, peel, and still remain red. This is a normal response as the abnormal cells are being destroyed.

Day 5-7: Some redness may be remaining, but healing continues and skin begins to clearer and smoother. Continue with gentle skincare.

Some patients may require more than a week of healing time with the redness and swelling, but resolves within the coming weeks.

Will I have any downtime?

The downtime varies depending on the extensiveness of the reaction. It is difficult to predict the type of reaction, and can be attributed to the amount of sun damage. You may experience redness, peeling, swelling, crusting, itchiness post treatment. This is normal and part of the healing phase post treatment.

What are some benefits of the treatment?

Treatment is done in our office
FDA approved. Treatments can be repeated if necessary without adverse long term effects. Scarring has not been reported in clinical trials.
Covered by most insurances.
Don’t have to apply a daily medication

Do I need to have a consultation before scheduling a treatment?

It is very important to have a consultation so that you can be thoroughly evaluated and educated on expectations and outcomes. This also allows your provider to review your medical history and take precautions as needed. This includes informing them of any oral antibiotic use such as tetracyclines as there may be associated side effects. If you have history of coldsores, you may need prophylactic treatment prior to your PDT treatment.

Connecticut Skin Institute