Final answer:
Warfarin should be held 48 hours prior to cardioversion to reduce the risk of bleeding.
Step-by-step explanation:
The drug that should be held 48 hours prior to cardioversion is Warfarin. Cardioversion is a medical procedure in which an electrical shock is used to restore the heart's normal rhythm. Warfarin is a blood-thinning medication that increases the risk of bleeding during and after the procedure. It is important to hold the medication to reduce the risk of complications.