Palonosetron is primarily used in the prevention and treatment of nausea and vomiting caused by chemotherapy, particularly in patients undergoing highly emetogenic chemotherapy (HEC) or moderately emetogenic chemotherapy (MEC). It is often administered before chemotherapy sessions to reduce the risk of acute and delayed nausea and vomiting, improving patient comfort and adherence to treatment. Additionally, it is used in the management of postoperative nausea and vomiting (PONV) in surgical patients, providing effective relief and enhancing recovery outcomes. Its long-acting properties make it a preferred choice in clinical settings for sustained antiemetic effects.