Slide show: Common baby rashes

Many parents expect their baby's skin to be flawless, but usually it isn't. Diaper rash, cradle cap, infant eczema and other rashes can affect your baby's skin. Fortunately, most baby rashes are harmless. They may require your attention, but need little or no treatment. In severe cases, your baby's skin rash may require medical care. Here's a look at common baby rashes, their causes and when your baby might need to see a doctor.

Cradle cap is a very common skin condition that appears as somewhat greasy, crusted, scaly patches on the baby's scalp. It usually occurs during infancy and usually isn't reddened or tender. Most infants have milder cradle cap than is demonstrated in the photo.

Cradle cap should disappear within a few months without treatment. Periodic shampooing and applying creams to loosen scales should help clear this condition faster. If cradle cap persists or seems severe, your doctor may suggest a medicated (antifungal) shampoo, lotion or other treatment.

Moisture, chafing and acid presence in soiled diapers cause diaper rash. To prevent the rash, change your baby's diaper as soon as it gets wet. Apply a protective cream or ointment with each diaper change. Check with your baby's doctor or nurse practitioner if the rash doesn't improve. Some diaper rashes are treated with anti-inflammatory creams and some with antifungal preparations.

This rash appears as fine, clear or red spots, typically on the forehead, face, folds of the neck, chest and arms. Often a result of overdressing, heat rash is common in infants during hot, humid weather.

To prevent heat rash, dress your baby in cool, lightweight clothing for hot weather. Air conditioning helps. When it's hot and humid, babies get just as uncomfortable as adults do. In spring and fall, as well as indoors in winter, layer your baby's garments so that you can remove them as the day heats up. Heat rash generally disappears without treatment.

Infant acne, consisting of whiteheads mainly on the face, usually appears during the first several months of life and can last a year or more.

To manage infant acne, wash your baby's face daily with mild, nonirritating and nondrying soap. If your baby has a severe case of acne, ask your doctor to recommend a safe medication.

If your infant has eczema (atopic dermatitis), you may first notice light red or tannish-pink patches of rough scaly skin. The patches later become red. Your baby may seem restless and irritable due to itching. Occasionally, the rash begins to ooze and crust over. A skin infection may follow.

In some infants, the rash can be traced to diet or a change in formula. Sometimes, the offender may be a laundry detergent, strong soap, fabric such as wool or excessive perspiration during hot weather. Treatment includes identifying and avoiding the irritant, avoiding extreme temperatures, and using bath oils, lotions, creams or ointments to lubricate the skin. See a doctor if these measures don't improve the rash or if the rash looks infected. Your baby may need a prescription medication.

Milia — tiny white "pimples" on the nose and chin — appear during the first few days of life and is normal for newborns. In fact, more than half of newborns have these little spots. After a couple of weeks, milia disappear without treatment.

A yeast infection is a persistent, bright red rash in the diaper region or other areas where skin touches skin. Yeast infections are caused by a microorganism (Candida albicans) that flourishes in a warm, moist environment. If your baby has a yeast infection, you'll need a prescription antifungal cream to treat it.