This study aims to evaluate whether the addition of probiotics can help reduce abdominal discomfort (such as diarrhea) in breast cancer patients receiving Abemaciclib treatment. Abemaciclib is an effective targeted therapy but often causes gastrointestinal side effects. While Loperamide is the standard treatment for diarrhea, this study explores if probiotics can provide additional relief and improve metabolic health.Participants will be randomly assigned to receive either probiotics or a placebo alongside their standard care. The study will monitor the frequency of abdominal symptoms and analyze blood samples to observe changes in metabolic factors.