Dandruff is a skin condition that mainly affects the scalp.[1] Symptoms include flaking and sometimes mild itchiness.[1][2] It can result in social or self-esteem problems.[4] A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis.[1]

Other namesPityriasis capitis, pityriasis sicca[1]
A microscopic image of human dandruff
SymptomsItchy and flaking skin of the scalp[2][1]
Usual onsetPuberty[1]
CausesGenetic and environmental factors[1]
Diagnostic methodBased on symptoms[3]
Differential diagnosisPsoriasis, dermatitis, tinea capitis[2][1]
MedicationAntifungal cream (ketoconazole), salicylic acid[2][1]
Frequency~50% of adults[1]

The cause is unclear, but believed to involve a number of genetic and environmental factors;[1] the condition may worsen in the winter.[5] It is not due to poor hygiene,[6] and the underlying mechanism involves the excessive growth of skin cells.[5] Diagnosis is based on symptoms.[3]

There is no known cure for dandruff.[7] Antifungal cream, such as ketoconazole, or salicylic acid may be used to try to improve the condition.[1][2] Dandruff affects about half of adults, with males more often affected than females.[1] People in all areas of the world are affected.[1] Onset is usually at puberty and it becomes less common after the age of 50.[1]