Cradle cap is a common skin condition that affects young babies. It is commonly present in the first three months of life, and is rare after the age of one year. It is a form of seborrhoeic dermatitis and appears as thick, waxy, yellow crusts on the baby's scalp.

Cradle cap is neither painful nor itchy and usually clears by itself after a few months. It is not contagious, and it is not caused by poor hygiene. Babies with cradle cap are otherwise well, but many parents prefer to remove the crusts because they do not like how it looks.

Cradle cap may appear in your baby's eyebrows. Scaly patches on other parts of the face or body are not cradle cap and should be checked by your GP or paediatrician. If the cradle cap starts to ooze or smell, the area may be infected and you should have your baby assessed.

If your baby has cradle cap, they may have:

• Yellow, greasy, waxy scales or flakes on the scalp, or sometimes the eyebrows
• Reddening of the skin, which sometimes occurs due to eczema developing underneath the cradle cap.

Although the cause is unknown, several factors may play a role in causing seborrheic dermatitis (or cradle cap in infants): abnormality of the oil glands and hair follicles, a yeast fungus with bacteria growing in the sebum, production of certain hormones, stress, change of seasons (outbreaks seem worse in winter) and fatigue. There is a known relationship with skin yeasts of Malassezia spp. This is thought to be due to a reaction to the yeast, rather than a simple infection. Overactivity in the sebaceous glands of a newborn may also be a factor.

Cradle cap is a form of dermatitis that causes inflammation of the oil glands in the skin, which are called the sebaceous glands. The type of dermatitis is called seborrhoeic dermatitis. Sebaceous glands help ‘waterproof’ the skin by making a slightly greasy substance called sebum. Babies are born with active sebaceous glands because they have been living in their mother's womb. Once a baby is about three months old, the sebaceous glands become inactive until puberty.

Sometimes, the skin under the crusts of cradle cap can become infected. The skin becomes redder and small blisters appear, and then pop and weep. This is caused by the same germs that cause impetigo (‘school sores’).

If this infection spreads, or your baby becomes unwell, make sure that you have your baby checked by a doctor. Your baby may need antibiotics to get rid of the infection. Unlike cradle cap, impetigo is highly contagious.

Cradle cap usually gets better on its own without treatment. However, the following steps may help it improve faster:

• Loosen the crusts by applying a light moisturising cream or lotion to the scalp. The next morning, wash your baby's hair with a baby shampoo, gently lifting the crusts off with a soft brush (an unused soft toothbrush can be good for this) or comb. Try this each day until your baby's scalp looks clearer.
• Use a mild anti-dandruff shampoo (only use for one to two weeks) if the other treatment is not working. Be careful, as some shampoos can be drying and can irritate a baby's skin. Take care not to get the shampoo in your baby’s eyes.

The cradle cap may come back, even when treated properly, because the glands can keep making too much sebum for a few months. If this happens, repeat the treatment.