Used primarily to prevent nausea and vomiting associated with chemotherapy and radiation therapy, especially in cancer patients. It is effective against both acute and delayed forms of chemotherapy-induced nausea and vomiting. Also utilized to prevent postoperative nausea and vomiting in surgical patients. Acts by blocking serotonin receptors in the central nervous system and gastrointestinal tract, providing long-lasting protection due to its extended half-life and unique binding properties.