Symptoms
For most teens and adults, dandruff symptoms are easy to spot: white, oily-looking flakes of dead skin that dot your hair and shoulders, and a possibly itchy, scaly scalp. The condition may worsen during the fall and winter, when indoor heating can contribute to dry skin, and improve during the summer.
A type of dandruff called cradle cap can affect babies. This disorder, which causes a scaly, crusty scalp, is most common in newborns, but it can occur anytime during infancy. Although it can be alarming for parents, cradle cap isn't dangerous and usually clears up on its own.
When to see a doctor
Most cases of dandruff don't require a doctor's care. But if over-the-counter (OTC) dandruff shampoos aren't helping, or if your scalp becomes red or swollen, see your doctor or a doctor who specializes in skin conditions (dermatologist). You may have seborrheic dermatitis or another condition that resembles dandruff.
Source: http://www.mayoclinic.com