Blue light therapy kills acne bacteria with specific wavelengths of blue visible light. It really works, but it's not a treatment suitable for babies.How Blue Light Therapy Works
In blue light therapy, first the skin is treated with a photosensitizing agent that makes it absorb more light. Then painless, non-burning low-intensity blue light is focused on the skin where there are blemishes. Acne bacteria contain blue pigments that absorb blue rays of a very specific wavelength. These pigments overheat and the acne die.
Great Home Blue Light Therapy Devices for Adults
Blue light can be a great way to stop active acne on adult skin. The Trophy Skin Blue MD Dermatologist Grade Blue Light Kit (retailing in the US for $199) and the Baby Quasar Light Therapy Device for Acne (retailing in the US for $299-309) are even available for treatment at home. But just because a product has the word "Baby" in its name does not mean you should use it to treat acne in your infant!
But Not for Babies
One of the reasons blue light is not for babies is that it requires the use of a photosensitizing chemical called aminolevulinic acid, or ALA. Creams of this kind of ALA (not to be confused with alpha-lipoic acid) can cause burning, itching, redness, and blistering. This is not an improvement for baby's skin.
Moreover, especially if your baby has golden, brown, or "black" skin tones, any kind of irritation can cause lasting discoloration of the skin, discoloration that is almost impossible to remove later. ALA in the eyes can cause permanent damage, too. Baby acne, on the other hand, usually resolves even if you don't treat it.
Just say no to blue light for baby acne. It's an adult technique that has no place in everyday infant skin care.