[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][7] and the underlying mechanism involves the excessive growth of skin cells.

[8] Antifungal cream, such as ketoconazole, or the keratolytic agent salicylic acid may be used to try to improve the condition.

[7] As the skin layers continually replace themselves, cells are pushed outward where they die and flake off.

While this species does occur naturally on the skin surface of people both with and without dandruff, in 2007, it was discovered that the responsible agent is a scalp specific fungus, Malassezia globosa,[19] that metabolizes triglycerides present in sebum by the expression of lipase, resulting in a lipid byproduct: oleic acid.

[21] In seborrhoeic dermatitis, redness and itching frequently occur around the folds of the nose and eyebrow areas, not just the scalp.

Dry, thick, well-defined lesions consisting of large, silvery scales may be traced to the less common condition of scalp psoriasis.

Inflammation and extension of scaling outside the scalp exclude the diagnosis of dandruff from seborrhoeic dermatitis.

[5] Dandruff scale is a cluster of corneocytes, which have retained a large degree of cohesion with one another and detach as such from the surface of the stratum corneum.

A corneocyte is a protein complex that is made of tiny threads of keratin in an organised matrix.

Antifungal treatments including piroctone olamine, ketoconazole (Sebizole), zinc pyrithione, and selenium disulfide (Selsun Blue) have been found to be effective.

Of all the antifungals of the imidazole class, ketoconazole has become the leading contender among treatment options because of its effectiveness in treating seborrheic dermatitis as well.

[28] Other than zinc pyrithione, the most common anti-dandruff actives (outside the US) and part of many cosmetic shampoos, are piroctone olamine and climbazole.