One recent innovation in the light of home acne treatment is acne light therapy, which is basically pointing a cone at your face that shoots out light at a certain frequency. The most prevalent wavelenghts for treatment are red and blue light, both of which are known for different results.
There have been a number of studies in recent years studying different light waves, and results so far are promising. The most effective for acne treatment appears to be blue light, which is the first product well look at.
Blue light is capable of killing acne vulgaris, which is the strain of bacteria that causes acne inflammation. One study tested this by administering blue light to only one side of patients faces, and then comparing acne between both sides after 12 weeks of treatment.
This study found an average of 39% difference between acne levels on each side, which is a significant reduction.
Another study used a similar method, but instead tested different types of acne. They found blue light to be effective for anything except nodulocystic acne lesions, which are the extreme form of acne that leaves deep inflamed bumps (aka nodules) and lesions on the face. For this level of acne, a strong prescription drug treatment such as accutane would be needed for effective treatment.
Another form of acne light therapy uses red light. This wavelength works differently, and encourages the growth of skin cells rather than kill bacteria. In addition to acne treatment, red light has been tested to stimulate wound healing and wrinkle repair.
For acne treatment specifically, red light was combined with ALA (5-aminolevulinic acid), which increases the skins photosensitivity (fancy way of saying that it makes the skin react more to light).
This study found a decrease in acne lesions over time, however, there were some significant side effects: temporary darkening of the skin, followed by development of follicullitis, which is an inflamation of hair follicles similar to acne. For this reason, current medical wisdom favors blue light over red light, though some treatments combine both.
Light therapy options include some home products, such as the Acne Lamp (which I have no personal experience with, though some swear by it). For clinical-grade results, dermatologists can administer treatment, with sessions typically running $100 to $200.
These are usually not covered by insurance, so if the price is prohibitive you should stick to over the counter treatments.