A Randomised Placebo Controlled Trial of Antiemetic Agents in Adult Emergency Department Patients with Nausea or Vomiting.

Many patients present to emergency departments with nausea and vomiting. There are many possible causes of nausea and vomiting, such as gastroenteritis, side effects of medications, or surgical conditions to name a few. Because of its many causes, emergency department nausea and vomiting is difficult to study and treat. Drugs used to treat nausea and vomiting are called antiemetics. Very few studies of emergency department nausea and vomiting have been performed. Evidence from other areas of medicine, including cancer and postoperative research, has been used to determine what drugs are used in the emergency department setting. The patients in such research however are different to emergency department patients, and so it is not possible to reliably transfer the evidence. We propose to study two drugs used in the emergency department for nausea and vomiting. We will compare them to each other and also to placebo (an inactive injection that looks the same as the study drugs). These two drugs are called metoclopramide and ondansetron. It is possible that the drugs currently used in emergency departments for nausea and vomiting are not more effective than placebo (inactive drug). Given that these drugs have side effects, it is important to find out if they work. To make sure patients are not potentially disadvantaged by getting placebo, I have excluded patients with very severe nausea or vomiting from this study. Also, if patients still have nausea or vomiting after 45 minutes from the start of treatment, they can get a “rescue” medication of intermediate dose Ondansetron. Since the two active drugs studied are well proven to work in patients with nausea or vomiting due to cancer therapies or post surgical patients, I have also excluded such patients from this study. Everybody involved in the trial will be blinded (not know which drug the subject is getting). The subject will be randomly allocated to which treatment they will get. This will help to ensure the results and conclusions are accurate. Subject response to the study drugs will be compared to each other and to placebo (inactive drug) to see which is the best drug for the treatment of emergency department nausea and vomiting.