What are some common scalp disorders?

Some common scalp conditions are dandruff, head lice, lichen planus, psoriasis and seborrheic dermatitis, states WebMD. Cradle cap usually affects infants from birth to 6 months old, and ringworm mostly affects children 3 to 7 years old.

Dandruff is dead skin in the form of white flakes that have built up and must shed, notes WebMD. It is not dangerous, but causes itchiness of the scalp. Using medicated shampoo can relieve dandruff. Dandruff is a mild form of seborrheic dermatitis. As seborrheic dermatitis worsens, the scalp turns red and oily.

Psoriasis is a skin condition that can show up anywhere on the body, including the scalp, notes WebMD. Doctors treat it with a steroid ointment.