How Long Does Fentanyl Stay in Your System?
Fentanyl stays in the body for about 3 days before it is out of your system. For additional information: http://www.prescriptiondrug-info.com/topics/how-long-does-fentanyl-stay-in-system/
Fentanyl can stay in your system for 74 hours. The time it takes to clear out of your system to vary depending on the amount and size of the person.
Like most narcotics, Fentanyl will be readable on drug tests from 2 to 5 days. The high from Fentanyl is much shorter, lasting less than an hour in most cases.