Update on anti-emetics for chemotherapy-induced emesis.

The need to control chemotherapy-induced emesis has stimulated research into anti-emetics. Emesis is not only unpleasant, but negatively impacts on global quality of life. The development of two new classes of drugs has been responsible for the major advances in anti-emesis. The 5 hydroxytryptamine3 (5HT3) antagonists in combination with dexamethasone significantly improved the control of acute post chemotherapy emesis, but delayed emesis which can last for several days was still problematic, yet its incidence was underestimated by clinicians. Both the control of acute and delayed emesis was improved when the neurokinin1 (NK1) receptor antagonists were added to 5HT3 antagonists and steroids. The complete control of delayed emesis was improved by 21% with little toxicity. The triple drug combination has become the standard of care for preventing the emesis associated with cytotoxic drugs of high emetic potential.