Blue light therapy is a noninvasive treatment for acne that uses light to kill certain bacteria on the skin.

A form of phototherapy, blue light treatments are FDA-approved for acne vulgaris that is moderate or has not responded to other therapies.

Blue light therapy can be carried out in a dermatologist's office or at home.

Fast facts on blue light therapy:

• Blue light therapy uses light in the blue wavelength range to kill the bacteria Propionibacterium acnes, or P. acnes, on the skin.

• There is no recovery time, and the treatment has relatively few, if any, adverse effects.

• Studies show moderate evidence for the efficacy of blue light treatments for people with mild to moderate acne.

• It should be noted that most studies on blue light therapy are small and do not report on long-term results. There is a lack of data for outcomes in cases of severe acne.