Jaundice is not actually a medical condition so much as a symptom. The yellowish appearance of the skin is because of an excess of bilirubin, a yellow-colored pigment in the blood. The liver ordinarily filters bilirubin, so jaundice is indicative of a failure of the liver.
There are two types of jaundice: infant jaundice, by far the most common, appears in newborns; adult jaundice is a much more rare condition, when the symptoms present in fully-grown adults.
Consult a doctor at the first sign of jaundice symptoms, regardless of whether the jaundice presents in infants or adults.
Discuss with a doctor, in the case of infantile jaundice, whether or not the case is severe enough to merit treatment. In many cases, infant jaundice is simply due to the child's liver not yet being mature enough to filter bilirubin, and it may not need treatment at all.
Seek phototherapy treatment in more serious cases of infant jaundice. In this case, your baby will be placed under a special light that emits blue-green light. This will alter the bilirubin in the baby's blood to make it so that it can be passed in urine and stool.
Call a doctor for immediate treatment if jaundice presents in an adult. Adult jaundice likely indicates a problem with the liver. In some cases, a tumor or gallstones will create a duct blockage that prevents the bilirubin from being flushed into the intestines; in other cases, anemia can cause bilirubin build-up. It's important to get to the root cause of jaundice before it causes more serious problems, so make an appointment as soon as possible.