Previous case reports describe the inadvertent administration of methylergonovine to newborns resulting in rare, life-threatening events including neonatal death. To our knowledge, no case reports exist detailing inadvertent methylergonovine administration in the emergency medicine literature. A newborn infant presented to the emergency department (ED) at hour five of life following methylergonovine administration with periods of apnea and cyanosis. The infant required intubation, mechanical ventilation, and a seven day neonatal intensive care stay. This rare case describes the potential for this error to occur in the community and heightens the vigilance of emergency medicine providers when caring for newborns in their first hours of life.