Yellowing of the eyes, which is medically known as "scleral icterus" or simply referred to as "jaundice," can be a sign of the liver disease. Both cirrhosis and hepatitis are known to turn the conjunctiva of the eyes a yellow color, according to WebMD. The term "scleral icterus" is a bit of a misnomer, since it is the conjunctiva and not the sclera that actually yellows with disease.
The yellow color is caused by an overabundance and buildup of bilirubin. Bilirubin is a compound that is made when hemoglobin breaks down. Hemoglobin is found in red blood cells and serves the purpose of carrying oxygen. Normally, a small amount of red blood cells in a healthy body die daily; new ones are made to replace them. The dead cells are removed by the liver, and in the process, bilirubin is made. Bilirubin is broken down by the liver and passed through the stool, according to MedlinePlus.
When the buildup of bilirubin becomes too much for the liver to handle, jaundice occurs. This usually occurs due to damage or overload of the liver, and is generally a signal that something is wrong in the liver, pancreas or gallbladder. While typically caused by liver disease, infections, cancer, blood disorders and the use of certain drugs can also cause jaundice.