Antiemetic agents

Abstract

Emesis is defined as the forcible emptying of gastric and/or intestinal contents.¹ Nausea and vomiting have many causes, including drugs (nitrous oxide, chemotherapeutic agents, opioids, etc.), radiation therapy, pregnancy, motion sickness, postoperative, pain, etc.² Postoperative nausea and vomiting (PONV) occur immediately in the recovery area or up to 24 hours postoperatively.² The incidence varies between 30% and 80%, especially if no prophylaxis is given.^2,3

PONV ranks high on the list of postoperative patient concerns.² It can result in wound dehiscence, aspiration, oesophageal rupture, dehydration, raised intracranial pressure, and pneumothorax due to the high pressures generated while retching.² The morbidity surrounding PONV itself is enough for anaesthesia to prevent its occurrence (prevention is better than cure). To adequately prevent and treat nausea and vomiting, it is essential to know the pathophysiology, receptors, and signalling molecules.