Two days and 7 hours ago I had PDT for cystic acne. Wish I'd listened more carefully, but I believe the Levulan only incubated for 15 minutes. Then I was under the light for 15 minutes. I believe through the goggles the light I saw was blue. Here I am, housebound, the new owner of a big hat, lots of Aquaphor, hydrocortisone, vinegar, and ice packs, and with nowhere to go because I turned down all jobs for the week. And yet: nothing! Not even pinkness, not even itching. What gives?
PDT and No Reaction Whatsoever?
Doctor Answers 1
PDT parameters need adjustment
Currently, there is no standard protocol for treating acne with PDT, so responses may differ depending on the following:
- the type of chemical used (Levulan versus Metvix)
- length of time the chemical is left on the skin before activation (incubation)
- the activating light source used (blue light versus red light versus IPL or laser).
- the duration of exposure to the light source
- the number of treatment sessions (commonly 3-4 total at 2 week intervals)
For severe facial cystic acne I have had the best results using red light and Levulan with 3 hour incubation. The specific parameters depend on the particular patient, the severity of their acne, and the severity of side effects the patient is prepared to tolerate. A more aggressive treatment can be quite painful and result in severe redness and crusting lasting a full week. Be sure to see a physician experienced in PDT.