Searching "Fentanyl vs morphine for acute pain" will give plenty of studies comparing the two. At a quick glance through a few of them, it appears the main diff

Searching "Fentanyl vs morphine for acute pain" will give plenty of studies comparing the two. At a quick glance through a few of them, it appears the main differences are faster onset, shorter duration, lower incidence of side-effects (primarily nausea), and less histamine release.