Potential study patients will be identified by an ED nurse or a member of the study team using the inclusion and exclusion criteria. ED nurses will be informed of the study by charge nurses who have been educated about the protocol by the research team. The purpose, content and logistics of the study will also be described to ED physicians participating in the study. Research assistants, when available, will be notified by cell phone or pager to see patient in the ED within 20 minutes. The attending physician or resident will be informed of the potential study patient. The attending physician or resident will give the research associate/member of the study team permission to discuss the study with the patient. If the patient is interested in participating in the study, the research associate/member of the study team will discuss the details of the study and review the consent form. It is likely the onset of treatment with DT or MET will be delayed 30 to 40 minutes due to the consenting process and study enrollment. The attending physician must agree to this delay.