Naloxone versus metoclopramide for the treatment of established postoperative nausea and vomiting in patients following general anesthesia with fentanyl supplementation--pilot study.

PONV can cause prolonged post anesthesia care unit (PACU) stay and unanticipated admissions following ambulatory surgery, therefore increasing medical costs1. Nausea and vomiting are also among the most unpleasant experiences associated with surgery and one of the most common reasons for poor patient satisfaction rating in the postoperative period2. Because PONV is multifactorial and several neurotransmitters are involved in the emetic response, effective management remains challenging.