A new class of antiemetic agents on the horizon

Management of chemotherapy-induced nausea and vomiting

Chemotherapy-induced nausea and vomiting are symptoms that cause major concern to oncology patients. This article explores the types of nausea and vomiting in the context of chemotherapy, and discusses their pathogenesis and management.

Optimising antiemetic therapy: what are the problems and how can they be overcome?

BACKGROUND

Management of chemotherapy- or radiotherapy-induced emesis has improved significantly following the introduction of the 5-HT3-receptor antagonists. Prophylactic use of these agents is recommended for the prevention of both chemotherapy- and radiotherapy-induced nausea and vomiting, given with a corticosteroid. Despite these advances, nausea and vomiting remain among the most feared and debilitating adverse effects of cytotoxic therapy. The shift towards a more elderly population of patients with cancer presents additional considerations for supportive care, with an emphasis on achieving control of nausea and vomiting, whilst minimising toxicity and avoiding drug-drug interactions. This review presents some of the key issues for consideration in optimising antiemetic therapy. The PubMed search engine was used to search for relevant literature (up to December 2004) and relevant international congress materials collected during 2003 and 2004.

SCOPE

While the early stages of nausea and vomiting are 5-HT-mediated, identification of a role for substance P in late emesis has led to the development of the NK1-receptor antagonist, aprepitant. As a new agent, the clinical profile of aprepitant is still being explored, including its interaction with concomitant medications. Patients who achieve good control of acute and late-acute nausea and vomiting have a reduced risk of experiencing delayed onset symptoms, emphasising the importance of prophylactic management with effective agents. Although the 5-HT3-receptor antagonists are widely considered to have equivalent efficacy, they vary in half-life and the nature of antagonism at receptors. Their metabolic profiles also differ, with cytochrome P450 (CYP) metabolism affecting their propensity for drug-drug interactions. Several sets of guidelines are available that outline recommendations for selection and use of antiemetic therapy. However, under-use of 5-HT3 receptor antagonists has been reported in both the radiotherapy and chemotherapy settings, and some commonly used doses may be suboptimal.

CONCLUSION

In optimising antiemetic therapy, wider implementation of guidelines is desirable, as is consideration of each patient's individual needs. Safety and tolerability of supportive care medications should be a key consideration, and cardiovascular warnings and the possibility of drug-drug interactions should be given sufficient consideration, particularly in view of the older age of the population with cancer.

The Next Generation of Chemotherapy-Induced Nausea and Vomiting Prevention and Control: A New 5-HT₃ Antagonist Arrives

First-generation serotonin receptor antagonists greatly improved the control of chemotherapy-induced nausea and vomiting (CINV) during the 1990s. A new class of agents, neurokinin-1 receptor antagonists, was introduced in March 2003 and produced even greater control of CINV when used in combination with a serotonin receptor antagonist and a corticosteroid. In July 2003, palonosetron, a new second-generation serotonin receptor antagonist that has greater potency and a longer half-life than first-generation serotonin receptor antagonists, was introduced. This clinical update reviews studies that were conducted to evaluate these new agents.

Antiemetic therapy in patients receiving cancer chemotherapy

PURPOSE/OBJECTIVES

To examine the currently available antiemetic medications and review their uses in the treatment of chemotherapy-induced nausea and vomiting (NV).

DATA SOURCES

Published articles and book chapters.

DATA SYNTHESIS

NV is a common yet potentially serious side effect of chemotherapy. Nurses must understand the physiology of NV, its impact on patients, and the proper use of antiemetic medications to effectively manage this problem. Antiemetic medications vary in mechanism of action, indications for use, and adverse effects.

CONCLUSIONS

Nurses are in a position to identify patients who are at risk for NV and to manage their care using accepted practice guidelines.

IMPLICATIONS FOR NURSING

Although practice guidelines have been established, the nurse's role in assessment and implementation of care is critical in the prevention and management of chemotherapy-induced NV.