Initially the skin is cleansed and light scaling is removed. Then the photo agent is applied to the affected skin. After short wait period that allows the photo agent to absorb, the patient would sit under a specialized illumination for a short period of time. The lamp is warm, but does not harm the skin.
After the treatment, patients should avoid sunlight, prolonged or intense light (e.g., tanning beds, sun lamps) on skin areas treated approximately 48 hours following treatment, whether exposed to illumination or not. You must wear sunscreen for 48 hours after treatment as your skin will be increasingly sensitized to light.
Local skin reactions from the light occur almost immediately after the first treatment. There may be some sensation of reddening of the skin at the application site, slight burning or irritation, but this indicates that the photo agent and light are working to deaden undesired cell growths. Cooling of the treatment area during and after PDT usually reduces the symptoms.
The healing process usually takes a few days. Once the crusts from the light treatment are gone, the skin appears smooth and returned to normal appearance.
The final results of the treatment will be examined by your doctor three months after your first PDT, to determine if all lesions/spots have been eliminated. If any remain, a second PDT treatment is recommended. Studies have shown that six out of ten patients treated with PDT did not require a second treatment. About 9 out of 10 patients who received one or two treatments with PDT were completely cleared of their spots and lesions.