Nausea and vomiting is a common complaint in the emergency department. Treatment is important for many reasons. In addition to patient comfort, there are adverse effects secondary to vomiting such as dehydration, metabolic alkalosis, Mallory-Weiss tears, and aspiration. Two mediations common used for nausea in ED patients include Ondanesetron and Metoclopramide.

This study will compare Ondansetron 4 mg vs 2 mg vs Metoclopramide 10 mg to look for efficacy in nausea and vomiting treatment for patients in the ED with many different causes. We will also look for cost effectiveness as well, since Metoclopramide is much less expensive than Ondansetron, which is less expensive at lower doses. There is little research about nausea medication in the ED literature even though these medications are used frequently in the ED for many causes of nausea.

Inclusion Criteria:

• 18 years or older with nausea and at least 1 episode vomiting in the last 12 hours presenting to the York Hospital Emergency Department

Exclusion Criteria:

• Patients known to have hypersensitivity to the drugs ondansetron or metoclopramide
• gastrointestinal hemorrhage, mechanical obstruction or perforation
• patients with pheochromocytoma
• seizure disorder
• patients receiving other drugs which are likely to cause extrapyramidal reactions such as butapherones and phenothiazines
• patients experiencing hyperemesis gravidum
• patients unable to understand the informed consent (intoxicated, Spanish speaking)
• prior antiemetics within 12 hours
• inability to perform visual analog scale
• renal dialysis