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Fentanyl Detection Time – How Long Does Fentanyl Stay In Your System?

Isaac Alexis, M.D., AAMA, AMP-BC

Medically reviewed by

Isaac Alexis, M.D., AAMA, AMP-BC

February 5, 2019

Fentanyl detection times can vary from one person to the next. When taken intravenously, fentanyl is able to be detected in the system for 11 to 22 hours after the last dose.

Fentanyl detection time can vary and will depend on personal factors as well as how it is used. Generally, fentanyl is able to be detected anywhere from 11 to 36 hours after the last dose is taken.

Fentanyl is a synthetic opioid drug that is used for severe pain and as an anesthetic. As a pain reliever, it is around 50 times more potent than heroin and 100 times stronger than morphine. Common street names for this drug include china girl, china white, china town, goodfellas, and apache.

While fentanyl is produced and prescribed legally in the United States, it is also a highly abused substance. According to the Centers for Disease Control and Prevention, there were more than 1,000 deadly overdoses between April 2005 and March 2007.

Fentanyl can be used in a number of ways, including by snorting, smoking, injecting, taking orally, and used as a patch on the skin. Fentanyl has a similar effect to other opioids such as heroin and oxycodone.

Factors That Affect How Long Fentanyl Stays In Your System

There are several factors that can influence how long fentanyl is detectable in the system. Each person is different and will metabolize the drug at a different rate. Additionally, how the drug is taken can affect how long the substance can stay in your system.

Other factors that affect how long fentanyl can be detected in the body include:

Age: Younger people are generally in better health and have faster metabolisms. This means that someone younger can typically break down substances like fentanyl faster than older people.

Height and weight: People who are taller and heavier tend to metabolize substances and toxins more slowly than people who are shorter and weigh less. This is typically true for most substances.

Health: A person’s overall health can also play a role in how long it takes to rid the body of fentanyl. People who are healthier have healthier organs, which makes it easier for the body to break down toxins. Individuals who are not in good health may take longer to metabolize and get rid of substances such as fentanyl.

Dose: Taking a large dose of fentanyl or taking multiple doses in a short period of time can increase the time the drug is in the body.

Frequency taken: Taking fentanyl on a regular basis can result in the drug being stored in the body. This means that someone who regularly takes fentanyl will have more of it in his or her system than someone who only takes it once.

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Fentanyl Drug Tests And Detection Time

How long fentanyl will stay in your system also depends on its half-life. The half-life is how long it takes for half of a single dose of fentanyl to leave your body.

If using fentanyl as a patch, its half-life will be around seven hours. This means it will take approximately three days for all of the drug to leave the body.

When taking fentanyl intravenously, its half-life is much shorter at two to four hours. This means it will only take around 10 to 20 hours for the drug to be out of the system.

As fentanyl is broken down by the body, byproducts known as metabolites are left behind. Metabolites can stay in the body much longer and can be detected by some drug tests after the drug itself has left the body.

Detection Time Of Fentanyl In The Blood

Fentanyl can only be detected in the blood for up to 12 hours after the last use. Blood testing is the least common way to test for fentanyl and is also not reliable in terms of detecting drug abuse.

Detection Time Of Fentanyl In The Urine

Advanced urine tests can detect fentanyl in the system for eight hours to a day after the last use. How long fentanyl is detectable in the urine greatly depends on personal factors such as weight and metabolism.

Detection Time Of Fentanyl In The Hair

Hair can detect fentanyl in the body far longer than any other type of drug test. It can also tell if a person has been abusing fentanyl for an extended period of time. Fentanyl can be found in the hair for up to three months after the last use.

Fentanyl Abuse And Overdose

Because fentanyl is such a strong opioid, it can be relatively easy to become addicted to the substance. Fentanyl is often found in street drugs such as heroin, so people can be exposed to the highly addictive substance without even knowing it.

Luckily, it’s limited medical use makes it harder to obtain, which prevents most people from abusing it on a regular basis. Regardless, fentanyl addiction is still possible and symptoms can include:

  • shakiness
  • insomnia
  • muscle weakness or stiffness
  • trouble walking
  • anxiety
  • depression
  • itchiness
  • slurred speech

Because of its potency, fentanyl has a high rate of overdose. In fact, some estimate that fentanyl may be responsible for nearly half of all drug-related overdoses in the nation.

Symptoms of a fentanyl overdose may include:

  • fainting
  • slowed heart rate
  • purple or blue extremities and lips
  • coma
  • hypotension
  • seizures
  • vomiting
  • respiratory arrest
  • death

Fentanyl overdose is an incredibly dangerous medical condition. If you suspect that someone has overdosed on fentanyl, get medical help as soon as possible.

Getting Help For Fentanyl Addiction

Addiction to opioids such as fentanyl can be difficult to overcome alone. Getting help is the best step you can take towards a drug-free and fulfilling life.

Inpatient drug rehab centers provide individualized programs that can help someone who is addicted to fentanyl. Each treatment center varies in its treatment methods, and most offer customized options to suit the needs of each individual.

Contact us today to learn more about the detection time of fentanyl in the body or getting help for an addiction to fentanyl.

Drug Enforcement Administration - Drugs Of Abuse

Centers for Disease Control and Prevention - Synthetic Opioid Overdose Data

National Institute On Drug Abuse - Fentanyl

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