Atopic dermatitis (AD) is a skin condition that may cause a rash and itching due to inflammation of the skin. Around one-third of patients with AD have had at least 1 incidence of prurigo nodularis (PN), which is characterized by intense, persistent itchy skin and sometimes pain with burning. In this study, the effectiveness of upadacitinib (UPA) will be assessed in participants with prurigo-type AD in a real world (RW) setting in Japan. UPA is an approved drug for the treatment of AD. Adults and adolescents who have been diagnosed with prurigo-type AD and prescribed UPA according to the label and practice in Japan will be enrolled in this observational study. The doctor's decision to prescribe UPA will be made prior to and independently of study participation. Approximately 200 participants will be enrolled in the study at 10 sites in Japan. Participants will receive extended-release oral tablets of UPA once-daily for 48 weeks. There will be no additional burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the course of the study at a hospital or clinic.