Cradle cap, also known as seborrheic dermatitis, is a common skin condition that affects newborns and young infants. It is characterized by a scaly, yellow, or brownish rash that typically appears on the scalp, but may also occur on the face, neck, and diaper area.

The exact cause of the cradle cap is not known, but it is believed to be related to the overproduction of oil in the skin, combined with a yeast or fungal infection. Cradle cap is not contagious and is not caused by poor hygiene.

A cradle cap is usually not harmful and does not require medical treatment, but it can be unsightly and may cause some mild discomfort or itchiness. The condition typically improves on its own within a few weeks to a few months, but there are several things that can be done to help manage the symptoms and speed up the healing process:

• Gently wash the affected areas with a mild baby shampoo, being careful not to scrub too hard or cause irritation.
• Brush the scalp or affected areas with a soft-bristled brush to help loosen and remove the scales.
• Apply a thin layer of baby oil or petroleum jelly to the affected areas to help moisturize the skin and prevent further scaling.
• Avoid using any harsh soaps, shampoos, or lotions that may irritate the skin.

If the cradle cap does not improve or becomes more severe, it may be necessary to consult with a healthcare provider for further evaluation and treatment. In some cases, prescription-strength medicated shampoos or topical creams may be necessary to help control the symptoms of cradle cap.

The cause of cradle cap isn't known. One contributing factor may be hormones that pass from the mother to the baby before birth. These hormones can cause too much production of oil (sebum) in the oil glands and hair follicles.

Another factor may be a yeast (fungus) called malassezia (mal-uh-SEE-zhuh) that grows in the sebum along with bacteria. Antifungal treatments, such as ketoconazole, are often effective, supporting the idea that yeast is a contributing factor.

Cradle cap isn't contagious, and it's not caused by poor hygiene.

Shampooing your baby's hair every few days can help prevent cradle cap. Stick with a mild baby shampoo unless your baby's doctor recommends something stronger.

Cradle cap usually doesn't require medical treatment, as it usually goes away on its own. In the meantime, wash your baby's hair once a day with mild baby shampoo. If the scaling is heavy, apply mineral oil to the scalp for a couple of hours before shampooing. Then wash the hair as usual and brush the scalp lightly with a soft brush to loosen the scale.

If frequent shampooing doesn't help, talk with your baby's doctor about products that might help, such as a low-potency hydrocortisone cream or a shampoo with 2 percent antifungal ketoconazole medication. Be sure the shampoo doesn't get in your baby's eyes, as it may cause irritation.

Don't use over-the-counter cortisone or antifungal creams without talking to your baby's doctor, because some of these products can be toxic when absorbed through a baby's skin. Dandruff shampoos that contain salicylic acid aren't recommended for use in babies either, because they can be absorbed through the skin.