Common causes of an itchy head and scalp include dandruff, head lice, psoriasis, seborrhea and ringworm, explains WebMD. Treatment for the itchy head and scalp varies according to the underlying cause.
Dandruff leaves white flakes of skin on the neck, head and shoulders, according to WebMD. Eczema or a fungal infection can cause it, and seasonal or hormonal changes may make it worse.
Head lice most often infest school-age children, explains WebMD. The tiny insects leave raw patches and itchy areas on the scalp. Psoriasis and seborrhea are two of the more common chronic skin conditions to cause an itchy scalp. Ringworm usually creates a circular rash with raised, red edges. A fungal infection that develops in the hair and on the outer layer of the scalp causes it.