Update and new trends in antiemetic therapy: the continuing need for novel therapies.

Chemotherapy-induced nausea and vomiting (CINV) continues to be one of the most feared side effects of chemotherapy. Inadequately controlled CINV can have a significant negative impact on quality of life and can in some cases compromise adherence to treatment. However, the repercussions of CINV for patients are often underestimated. Advances in our understanding of the physiology of CINV and the identification of risk factors have greatly contributed towards improvements in the control of CINV. A number of antiemetic agents are currently available for the prophylaxis and treatment of CINV, including 5-hydroxytryptamine 3 receptor antagonists corticosteroids, neurokinin 1 receptor antagonists, dopamine receptor antagonists, benzodiazepines, neuroleptics and cannabinoids. With the correct use of these agents, CINV can be prevented to a great extent; however, adherence to guidelines is disappointingly low. Furthermore, a significant number of patients still experience nausea and vomiting despite optimal treatment. More effective therapies are, therefore, greatly needed, with the ultimate goal of attaining complete control of CINV. This review focuses on the current understanding of CINV, problems associated with its management and the status of promising antiemetic therapies.