Effects of Synbiotic Supplementation on Gastrointestinal Symptoms, Appetite, and Nutritional Recovery in Patients After Autologous Bone Marrow Transplant

Inclusion Criteria:

* Adult patients aged 20 to 65 years with hematological malignancies.
* Having undergone successful autologous bone marrow transplantation with confirmed neutrophil and platelet engraftment on day 30 post-transplant.
* Hematologically stable, clinically defined and laboratory-confirmed on day 30 post-transplant by:
* Neutrophil engraftment: Absolute Neutrophil Count (ANC) \>= 1,500/mcL (or \>= 1.5 x 10\^9/L) maintained for at least 3 consecutive days without hematopoietic growth factor support.
* Platelet engraftment: Platelet count \>= 20,000/mcL (or \>= 50,000/mcL according to institutional safety protocols) sustained without platelet transfusion for at least 7 consecutive days.
* Hemoglobin stability: Hemoglobin level \>= 8.0 g/dL without active bleeding or acute transfusion requirement.
* Discharged from the hospital and capable of oral intake and adherence to the daily supplement regimen.
* Capable of providing written informed consent.

Exclusion Criteria:

* Pre-existing severe gastrointestinal disorders (e.g., inflammatory bowel disease, active enteritis, or history of colorectal surgery/resection).
* Severe renal or hepatic impairment (e.g., pre-existing documented history or established clinical diagnosis of advanced renal failure, active requirement for renal replacement therapy, or decompensated liver disease, verified directly from institutional medical records).
* Active, prolonged high-dose systemic corticosteroid therapy or uncontrolled diabetes mellitus that may independently alter gastrointestinal motility, mucosal integrity, or appetite regulation.
* Known allergies or hypersensitivity to any component of the synbiotic formulation.
* Current or regular use of other commercial probiotic, prebiotic, or synbiotic supplements within 30 days prior to enrollment.