There are many possible causes of yellowing skin. Among the most common causes are conditions such as jaundice, a liver condition, and uremia, a kidney condition. Sometimes a condition called hypothyroidism, which is marked by an improperly functioning thyroid, is at fault. Additionally, the application of a topical antibiotic ointment called tetracycline may temporarily cause yellow skin.
One of the most likely causes of yellow skin is a condition called jaundice. When a person has jaundice, his skin develops an abnormal yellow coloring because high levels of bilirubin are in his bloodstream. Bilirubin is produced when the liver processes red blood cells. The liver usually removes bilirubin out of a person’s blood, and the bilirubin leaves the body in the stools. When there are problems with a person’s liver or its ability to process bilirubin, it can build up in the skin and cause yellowing.
A condition called uremia may also cause discoloration of the skin that may give it a yellow appearance. Uremia is a condition that develops when a person’s kidneys do not do an effective job of filtering. This inadequate filtering leads to a buildup of urea, which is a chemical in urine, and other waste products in a person’s blood. In addition to the yellowing of the patient’s skin, this condition may also cause such symptoms as nausea and vomiting, headaches, fatigue, drowsiness, and muscle cramps and twitching. It may cause itching as well.
Sometimes medication is the cause of yellowish skin. For example, a person may use a topical form of tetracycline for the treatment of a skin infection. While the medication may work, it may also cause the skin to appear yellow. Fortunately, however, the medication does not permanently discolor the skin. An individual can usually clear it by washing his skin with soap and water. Since the yellowing of the skin is not harmful in such a case, doctors often recommend keeping the medication on for as long as possible before washing it off.
Hypothyroidism is another condition that is associated with yellow skin. This condition is a result of a thyroid gland that does not produce adequate amounts of hormones. In addition to developing yellow skin, a person with this condition may become overly sensitive to the cold, fatigued, or depressed. His hair and fingernails may become weak and dry, and he may suffer from pain and stiffness in the muscles and joints. Constipation, weight gain, and high cholesterol may also develop as signs of hypothyroidism.