In March 2006, the U.S. Food and Drug Administration (FDA) tightened access to isotretinoin medications. Better known under brand names such as Accutane and Claravis, isotretinoin had become a highly popular and effective treatment for acne. But amid concerns about birth defects following fetal exposure to the drug, the FDA instituted the iPLEDGE program, which monitors the prescription process more carefully [source: Hampton].
In part due to those new regulations, dermatologists began paying more attention to alternative acne therapies, specifically laser and light treatments [source: Meville]. These procedures involve exposing affected skin areas to various types of infrared lasers and high-intensity lights to eliminate the acne-causing bacteria.
Although dermatologists are still conducting clinical trials to assess effectiveness, colored light therapies, better known as photodynamic therapies or PDT, hold promise for temporary acne relief. The technology applies the beneficial effects of sunlight on acne-affected skin without the harmful ultraviolet rays. A typical PDT schedule requires around eight 15-minute sessions over the span of four weeks.
The various types of PDTs use either high-intensity red, green or blue lights; blue light therapy has been the most widely studied of the three. PDT works by killing Propionibacterium acnes, or P. acnes bacteria, which infects and inflames acne lesions. By exposing acne pustules to the high-intensity light, it activates chemicals in the P. acnes called porphyrins. The porphyrins react with the light to produce free radicals, highly reactive groups of atoms with unstable electron pairs [source: Kaufman]. Those volatile free radicals then destroy the P. acne bacterial cells, allowing the skin to heal.
Small-scale studies have demonstrated significant acne relief from PDT. However, dermatologists and insurance companies haven't all seen the light in terms of its long-term success rates.