What is Photodynamic Therapy?

Photodynamic therapy is a process by which a photosensitizing drug and light device are used in combination to destroy or damage only the target cells in the skin, while preserving surrounding tissue.
It works like this. A drug that is capable of attracting light to the target cells (pre cancerous cells according to the current FDA approval) is placed on the skin. This drug (amino levulanic acid or ALA) is preferentially absorbed into the fast growing pre-cancerous cells. After an incubation period (a waiting period that allows the drug to absorb into the target cells) the excess ALA is removed from the surface of the skin.
Then, using a laser, Blu light or IPL the photosenstized drug (the ALA) is "activated". This means that the drug in the target cells absorbs more of the light from the laser, IPL or Blu-light, causing the target cells to heat up and be destroyed. This selective targeting of the precancerous cells is why this treatment is unique and the basis for how it works.

Photodynamic therapy otherwise known as PDT utilizes Levulan (levulinic acid, a naturally occurring breakdown compound of hemoglobin, part of red blood cells) and Blue light (~410nm wavelength). PDT is indicated by the FDA for actinic keratoses. There have been several published reports demonstrating efficacy for PDT for acne, acne rosacea, sebaceous hyperplasia, cosmetic benefits, e.g. collagen production. Depending on the aggressiveness of the protocol, PDT can have up to 7 days of red, scaly changes as if one has gone through sunburn reaction. A series of 4 PDT's, 4 weeks apart can definitely make acne prone skin better by helping to shrink oil glands, minimizing colonies of bacteria responsible for acne and thereby making conventional acne therapy work even better. If expense and downtime are of minimal concern, PDT can be combined with IPL under the supervision of experienced board-certified dermatologists to achieve significant rejuvenation and reduction of sun damage.

Photodynamic therapy is a chemical reaction FDA-approved for the treatment of actinic keratoses.  PDT can also be used to treat acne, rosacea, broken blood vessels, enlarged oil glands, and brown spots.  PDT describes a chemical reaction that occurs when a solution (Levulan) in the presence of oxygen is activated by light.  Abnormal skin cells (such as precancerous cells) are targeted and destroyed, revealing improved skin.