Weepy, yellowish scales that dry to a crust, called cradle cap, occur in about 40 percent of children in the first 3 months of life. The area can also get slightly red, but though it may look irritated, it does not itch. Most cases of cradle cap will clear up on their own by the time your baby is 8 to 12 months old, and often sooner, whether you treat it or not. But most parents want to do something because cradle cap looks so yucky.
To get rid of the thick scales, first soften them. Warm a bottle filled with olive, mineral, or baby oil in warm water. (Don't heat the oil in the microwave or you might make it hot enough to burn your baby.) Apply the oil to baby's scalp about 15 minutes before you wash her hair. Then use a mild dandruff shampoo and rub the scales gently with a soft brush, such as a baby hairbrush or toothbrush. The area usually looks better quickly, though some scales may remain.
In 10 percent of cases, cradle cap spreads to the face, behind the ears, and to the neck, armpits, and diaper area. If this happens, your doctor can suggest an over-the-counter cortisone cream to use twice a day for no more than a week (prolonged use of cortisone creams can alter skin texture and pigment).
When to Worry:
If the rash does not respond to simple measures or gets worse instead of better, your baby may have a secondary yeast infection. Consult your pediatrician for prompt prescription treatment.