Photodynamic and Acne
PDT or photodynamic therapy is the use of a chemical solution and a source of light to kill off the bacteria responsible for the painful lesions of acne. PDT uses a photosensitizing agent that requires a specific form of light. The combination of these two components gave rise to the term PDT.
In the United States, visible blue light is used to treat inflammatory acne. Visible blue light is:
- Narrow band
How Does Photodynamic Work on Acne?
To understand its mechanism, a review of how acne comes to be is necessary. Acne is primarily a hormonal condition wherein the skin undergoes increased sebum production. Sebum is the natural oil produced by sebaceous glands. It is responsible for keeping skin supply and hair naturally shiny.
When there is increased free androgen in the body, the sebaceous glands start to product more and more sebum. Some of the sebum plugs the skin’s pores. The pores then begin to accumulate the dirt of daily living. More dirt means bacteria. P. acnes are responsible for causing acne in children and in adults.
Now, the bacteria P. acnes have a byproduct called porphyrins. Think of porphyrins as sweat in humans. It’s the byproduct of metabolic processes. Metabolic processes are biological processes that make use of raw substrates to produce energy.
Now, the visible blue light that is used on acne activates these byproducts of cell metabolism. When these are activated, the P. acnes die immediately. When the bacteria no longer exists, the lesions, nodules and pustules begin to subside and heal.
Photodynamic Acne Treatment
PDT is a straightforward process. A healthcare professional administers the chemical known as amino levulinic acid to the affected skin. After administration of the photosensitizing agent, the chemical is allowed to seep into the areas that have the most damage due to acne. In short, the ‘spy’ is allowed to penetrate the enemy territory first before the strike. After a quarter of an hour or a full hour, the visible blue light is then released.
The use of the visible blue light usually takes ten minutes. After ten minutes, the skin is allowed to rest. Two main components are required from the visible blue light:
These two main components are responsible for the antimicrobial action of PDT.
Photodynamic Side Effects on Acne
As with all treatments for inflammatory acne, there have been some document side effects and disadvantages with the method. The milder side effects are the following:
- Increased incidence of sunburn and skin peeling
- Temporary pigment changes in the skin
- Dryness or scaling
Some disadvantages are:
- Some forms of acne may not respond to PDT
- Continued treatment is necessary to prevent recurrence of P. acnes