Herpes Zoster and Venous Thromboembolism Following Upadacitinib Treatment for Severe Atopic Dermatitis.

New medications targeting the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway have been developed through emerging biologics research. However, due to documented adverse effects, including herpes zoster (HZ) and venous thromboembolism (VTE), an extensive patient workup and counseling are necessary before prescribing. We present the case of an 81-year-old patient with severe atopic dermatitis on upadacitinib, a selective JAK1 inhibitor, who developed HZ and VTE, requiring hospitalization. This study emphasizes the need for further research, continuous monitoring, and risk management for HZ and VTE in patients undergoing upadacitinib treatment, especially in high-risk populations.