Double Challenges for Scalp Health: A Review of the Pathogenesis and Treatment Strategies of Coexistence of Seborrheic Dermatitis and Androgenetic Alopecia.

Androgenetic alopecia (AGA) and seborrheic dermatitis (SD) are two common scalp disorders that frequently impair the quality of life and may coexist in a subset of patients across all genders. SD presents in 40%-50% of all patients diagnosed with AGA. Although these conditions are traditionally discussed separately, increasing evidence suggests that they may share overlapping pathogenic factors, including androgen-driven sebum hypersecretion, imbalance of the scalp microecology, barrier dysfunction, and inflammatory signaling. We propose an integrated framework for understanding SD-AGA coexistence, emphasizing the interplay among endocrine influences, sebum alterations, microbial imbalance, and inflammatory activation. Therefore, the management of patients with coexisting AGA and SD should move beyond single-target approaches and emphasize the restoration of scalp homeostasis, control of inflammatory cascades, and integration of antiandrogen therapy through comprehensive, individualized treatment strategies. This review may offer a new perspective for the combined management of these dual scalp disorders.