Psoriasis, a chronic inflammatory dermatosis, represents a significant clinical challenge due to its complex pathogenesis and the limitations of existing therapeutic strategies. Current psoriasis diagnoses are primarily clinician-dependent, with instrumental diagnostics serving as adjuncts. Ongoing research is progressively deciphering its molecular underpinnings; the future of psoriasis diagnostics may involve genetic and immunological profiling to pinpoint biomarkers, enabling more accurate and timely interventions. The administration of psoriasis medications, whether oral, injectable, or topical, is associated with a range of side effects and compliance issues. Topical medications, despite their advantages in patient compliance and reduced systemic side effects, are hindered by the altered skin barrier in psoriasis, which impedes effective drug penetration and retention. In recent years, the development of novel transdermal drug delivery systems represents a promising frontier in psoriasis management. Nanotechnology-, microneedle- and dressing-based systems have demonstrated the potential for improved skin penetration, enhanced bioavailability, or extended retention time. Here, we will focus on the latest insights into the etiology, diagnostic methodologies, and therapeutic approaches for psoriasis, with a particular emphasis on the evolution and challenges of novel transdermal drug delivery systems.