Riboflaven and bilirubin response during phototherapy.

Twenty-four jaundiced neonates were studied, 12 in the treatment group and 12 in the untreated group. Patients were randomly selected to receive oral riboflavin. The mean 24-hr bilirubin decrease was determined during phototherapy. Blue light (420-470 nm) energy ranged from 6-10 muW/cm2. The observed 24-hr bilirubin decreased was compared with the expected decrease based on an energy-dose-response relationship. Riboflavin-treated infants received either 6-7 mu W/cm blue light energy or 810 muW/cm (same as control group). Those infants receiving less energy than the control group (8-10 muW)cm2 had a mean 24-hr bilirubin decrease (3.05 mg/100 ml/24 hr) equal to the control group (3.09 mg/100 ml/24 hr). Those riboflavin-treated infants receiving energy equal to the control group showed a greater decline (5.2 mg/100 ml/24 hr) in their mean 24-hr bilirubin. Although effective, additional in vivo studies are required to clarify the full effects, especially on DNA, of using photosensitizers such as riboflavin in the presence of bilirubin and blue light energy (420-470 nm).