Emergency medicine is the medical specialty concerned with the care of illnesses or injuries requiring immediate medical attention. Emergency physicians (or "ER doctors") specialize in providing care for unscheduled and undifferentiated patients of all ages. As frontline providers, in coordination with emergency medical services, they are responsible for initiating resuscitation, stabilization, and early interventions during the acute phase of a medical condition. Emergency physicians generally practice in hospital emergency departments, pre-hospital settings via emergency medical services, and intensive care units. Still, they may also work in primary care settings such as urgent care clinics.
Sub-specialties of emergency medicine include disaster medicine, medical toxicology, point-of-care ultrasonography, critical care medicine, emergency medical services, hyperbaric medicine, sports medicine, palliative care, or aerospace medicine.