Atopic dermatitis (AD) is a skin condition that may cause a rash and itching due to inflammation of the skin.

Upadacitinib is an approved drug for treating AD. Approximately 1000 adolescents and adult participants who are prescribed upadacitinib by their physician in accordance with local label will be enrolled in up to 40 sites in China.

Participants will receive oral upadacitinib tablets as prescribed by their physician according to their routine clinical practice and local label. Participants will be followed up for approximately 12 months.

There is expected to be no additional burden for participants in this trial. Participants will attend regular visits during the study at a hospital or clinic according to their routine clinical practice.

Inclusion Criteria:

• Adolescents (body weight >= 40 kg at the Baseline Visit for patients between >= 12 and < 18 years of age) and adults at the time of enrollment.
• Clinical diagnosis of moderate to severe atopic dermatitis at the time of enrollment.
• UPA treatment is indicated for AD and prescribed as per Chinese label / SmPC.
• The decision to prescribe UPA is made prior to and independent of study participation.
• The participant should not be treated with UPA prior to this study.
• Participants who are willing and able to participate in the collection of patient-reported data, including ePROs and eDiary via apps.
• The participant (legal representative for adolescents) voluntarily signed an informed consent before any study-related activities are conducted.

Exclusion Criteria:

• The participant is currently participating in interventional research (not including noninterventional study, observational study, or registry participation).
• Any circumstances that the investigator believes may limit the patient's participation and compliance with study procedures.

Adolescent and adult Chinese participants with atopic dermatitis (AD) who are prescribed Upadacitinib by their physician according to their local label.