Granisetron hydrochloride is primarily used as an antiemetic to prevent nausea and vomiting caused by chemotherapy, radiation therapy, and post-operative conditions. It is particularly effective in managing acute and delayed nausea associated with highly emetogenic chemotherapy agents. The drug is administered orally, intravenously, or via transdermal patches, offering flexibility based on patient needs and treatment protocols. It works by blocking serotonin receptors in the gastrointestinal tract and the brain, which are involved in triggering the vomiting reflex. Granisetron hydrochloride is favored for its high efficacy, minimal side effects, and ability to improve the quality of life for patients undergoing cancer treatment or surgery. It is also used in palliative care to alleviate nausea in terminally ill patients.