While a vitamin K deficiency can be dangerous, especially to infants that may easily suffer from extensive hemorrhaging, an overdose can be as equally detrimental. Newborns that are administered too great a dosage of vitamin K3 can suffer from kernicterus, a form of severe brain damage that may produce decreased movement, loss of appetite, seizures, deafness, mental retardation, and even death. This condition is associated with an abnormally high concentration of bilirubin, a bile pigment, in the tissues of the brain, which can be caused by the presence of K3. For this reason, K3 is less often utilized medically than it was in former times.