Depressive Disorder, Secondary

This is a single-center, prospective, randomized, dose-escalation Phase II clinical study. A total of 46 patients with newly diagnosed depression following allogeneic hematopoietic stem cell transplantation (allo-HSCT) will be enrolled. Participants will be randomly assigned to receive different doses of Xiaochaihu Granules in addition to standard post-transplant care for 100 days. The primary objective is to evaluate the efficacy of Xiaochaihu Granules in improving depressive symptoms. Secondary objectives include assessment of safety and clinical outcomes such as event-free survival (EFS), graft-versus-host disease (GVHD), infections, and other transplantation-related complications.