What is the Principle of Blue Light Therapy?

Question

My child has jaundice. What is the principle behind blue light therapy for treating jaundice, and how long does it usually take?

Answer

Blue light therapy, also known as phototherapy, is a simple method to reduce serum unbound bilirubin. It primarily involves using specific wavelengths of light to transform the lipid-soluble unbound bilirubin in a newborn’s blood into a water-soluble isomer. This process does not require metabolism through the liver and can be easily excreted from the body through bile or urine, thereby lowering the bilirubin levels. Since jaundice is caused by the accumulation of bilirubin in the body leading to skin yellowing, blue light therapy is one of the commonly used methods for treating jaundice.