Treatment of seborrheic dermatitis of the scalp

Summary Background  Seborrheic dermatitis and dandruff are common conditions dominated by flakes and itch symptoms. Beyond these observable conditions, the epidermis is highly perturbed and in an inflammation‐driven hyperproliferative condition. Aims  This review covers current etiologic models and therapeutic strategies. Conclusion  Etiology has been controversial in the past due to the search for a singular cause. There are three interrelated factors: Malassezia yeast, sebaceous lipids, and a group of host factors. The yeast and sebaceous lipids interact to yield an inflammatory initiator that leads to hyperproliferation within the epidermis; immature stratum corneum cells are dislodged as large clumps rather than a normal desquamative process. While many therapeutic strategies are theoretically possible, current technology is centered around controlling the Malassezia population. The most convenient and therefore most common format is the shampoo. A wide range of active materials are available; some are more effective than others. Even within a given active, product pharmacology can have a substantial impact on the delivered efficacy, with factors such as amount deposited on the scalp surface and bioavailability of the deposited material being relevant. Beyond choice of active and effective scalp delivery, product usage habits can substantially modulate the efficacy realized by the user.