This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intravenous Anesthetic Agents, Subject name: Anaesthesia
Which of the following intravenous anesthetic agents causes highest incidence of nausea & vomiting: 
Select and explain. 
A. Thiopentone, B. Propofol, C. Etomidate, D. Ketamine
C: Etomidate
Answer: C: Etomidate 
Explanation: Etomidate can be used in the treatment of endogenous hypercoisolemia. This is due to its ability to inhibit the enzyme 11b-hydroxylase, which results in decreased biosynthesis of coisol. Etomidate has the highest incidence of postoperative nausea and vomiting. Etomidate can be safely used in neurosurgical procedures. It is also the anesthetic induction agent of choice to reduce increased ICP when maintenance of cerebral or coronary perfusion pressure is impoant. Etomidate is the most cardiac stable induction agent and is the agent of choice in coronary aery disease, cardiomyopathy and cerebral vascular disease.