Fentanyl is one of the most potent prescription drugs on the market. It is used to treat severe pain and can be fatal in small doses. It is also being illegally mixed with other drugs to produce illicit opioids that are killing thousands of people through overdoses. Fentanyl can be found in many forms including patches, pills, injections, and powders. It has been linked to recreational drug use and is a leading cause of accidental overdoses. Fentanyl is 80-100 times more potent than morphine and is even more effective at causing addiction and overdose.
How long fentanyl stays in urine depends on the amount and frequency of drug usage, hydration level, body weight, toxicity levels, and metabolism rates. Depending on these factors, the detection window for fentanyl and its metabolite norfentanyl can range from 24 to 72 hours after use. Chronic users can have fentanyl remain in their system for much longer, as the drug may become sequestered into the fat cells and other tissues.
While saliva tests and blood tests can detect fentanyl, urine tests are the most common for drug screening in medical settings. Urine is easy to test, provides adequate sensitivity, and has a longer detection window than serum (which is associated with blood work).
Other types of drug testing, such as sweat, hair, and salvia tests can detect fentanyl as well but are less commonly used. Fentanyl and its metabolites can also be detected in the hair up to 90 days after the last time the user took the drug.