Diagnosis and Management of Seborrheic Dermatitis

Seborrheic dermatitis (SD) presents a common chronic inflammatory skin disorder that mostly concerns young adults in areas rich in sebaceous glands (scalp, face, and trunk). SD may appear as mild patches to diffuse scalp scaling in adolescents and adults. However, in infants, it mainly occurs on the scalp as yellowish, scaly patches ("cradle cap").

Several environmental triggers may promote SD development, along with fungal colonization by Malassezia spp., sebaceous gland activity, as well as immunosuppression, endocrine, neurogenic and iatrogenic factors in adults. In comparison, early occurrence in the first trimester indicates the role of boosted sebaceous gland activity from maternal hormones, along with cutaneous microbiome alterations, in children. 

SD is usually diagnosed clinically, and specific laboratory and/or instrumental investigations are seldom required. Treatment aims to modulate sebum production, reduce skin colonization by Malassezia spp., and control inflammation. In adults, topical antifungals (ketoconazole, ciclopirox, miconazole) or anti-inflammatory (mild-to-moderate potency corticosteroids) or keratolytic/humectant (propylene glycol) agents are used to treat mild-to-moderate scalp SD. While recommended topical therapeutic options for mild-to-moderate facial or body areas SD encloses topical ketoconazole, ciclopirox, clotrimazole, mild-to-moderate potency corticosteroids, lithium succinate/gluconate, and topical calcineurin inhibitors (off-label use). The severe and/or resistant cases require systemic antifungal drugs (terbinafine, itraconazole) and UVB phototherapy as a choice. In children, sparse scientific evidence supports the effectiveness and safety of topical drugs, and "cradle cap" is usually successfully managed with baby shampoos enriched with emollient agents and vegetable oils. Alternatively, like adult scalp SD, medical device shampoos with anti-inflammatory and antifungal properties containing piroctone olamine, bisabolol, alyglicera, and telmesteine may be employed. Outside pharmacological treatments, an appropriate cosmetic approach, if correctly prescribed, is likely to improve therapeutic outcomes.

Takahiro Suzuki, Tomohiro Seki, Toshinobu Seki. Study on a Novel Transdermal Therapeutic System that Combines the Achievement of Supersaturation by pH-shift Method and User–Activated System. Journal of Pharmaceutical Innovation. 2020;15: 1537-1548.