We performed a retrospective review of the charts of 252 adult, non-traumatic, prehospital cardiac arrest patients treated over a one-year period in order to assess the effectiveness of intravenous (IV) and endotracheal (ET) administration of epinephrine (0.5–1.0 mg) (EPI) in assisting restoration of a spontaneous pulse. Patients initially receiving IV-EPI were more likely to develop a spontaneous pulse earlier than those receiving a similar dose ET (7.3% vs 0.9%; p<0.01. In those patients who received a second dose of EPI, six (2.9%) regained a spontaneous pulse; each had been treated previously with IV-EPI. None who required a third dose of EPI regained a spontaneous pulse. In total, only five (2%) patients survived to discharge. We conclude that, in our system, patients who receive the currently recommended dose of EPI to treat cardiac arrest have a poor prognosis, and that IV-EPI is associated with a higher incidence of return of a spontaneous pulse compared to those treated ET.