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How Long Does Fentanyl Stay in Your System?

Fentanyl is becoming notorious for its role in the sharp rise in opioid overdoses across the nation. But how long does this drug, which is 50 times more potent than heroin, stay in your system?

You may be surprised to know that trace amounts of fentanyl can hang around in your body for months after the drug’s effects wear off. Even after your body shows no signs of past fentanyl use, drug tests can show that you have used the substance.

Lab tests come in 4 main types:

  • Urine
  • Hair
  • Blood
  • Saliva

How Long Does Fentanyl Stay in Your Body?

When you are thinking about how long fentanyl stays in your system, you need to consider three things: The drug’s half-life, your own body’s ability to break down toxins, and what drug test is being used.

Below are some guidelines to follow when you are considering the detection times for fentanyl by various lab tests. Remember that these times are not the same for everyone, due to differences in how each person’s body processes toxins like fentanyl.

How Long Does Fentanyl Stay in Your Urine?

If you know you’re going to be subjected to drug screening, you’ll want to know how long fentanyl stays in your urine. Lab tests can check for trace amounts of fentanyl itself, as well as for the metabolites that your body produces to break it down.

Studies show that fentanyl and its metabolites can be detected via urine testing for 4 days or longer. Most drugs are only detectable for 2-3 days via urine sampling.

Urine testing is the most common type of drug test. It is particularly common in the workplace. This is mostly because the tests are cheap and they are not invasive at all. Plus, compared to many other forms of testing, they can detect drugs like fentanyl for long periods of time.

You can’t be sure that your drug test will use a urine sample. There are three more types of tests that are also quite common.

How Long Does Fentanyl Stay in Your Hair?

Hair testing can detect fentanyl for up to 3 months after the last time taken. Because of the extremely long detection time of hair tests, fentanyl users cannot ensure a negative test result just because they’ve been clean for a week or two.

Hair tests are, however, rarely administered. They are more expensive than most other tests, and tend to be less accurate. Plus, they require the plucking of a hair from somewhere on the head or body, which is more invasive than simply asking someone to urinate in a cup.

How Long Does Fentanyl Stay in Your Blood?

Fentanyl has an 8-10 hour half-life. This means that half the drug is removed from your body after an average of 8-10 hours from your last dose. But drugs like fentanyl stay in the bloodstream in trace amounts for much longer than their half-life.

Fentanyl can be found by blood tests for about 48 hours after the last dose. If you are concerned about workplace testing, it is unlikely that you will be subjected to a blood test.

Blood tests are highly invasive but very accurate. For this reason, they are common in law enforcement and legal environments, but very rarely found in the workplace.

How Long Does Fentanyl Stay in Your Saliva?

Fentanyl is not consistently detectable via saliva testing. Saliva tests are taken by swabbing the cheek. They are commonly used by law enforcement in the field.

Fentanyl and its metabolites might be found by a saliva test for a couple of days after the last use, but this method of testing has been shown to be particularly ineffective for this drug.

Factors That Affect How Long Does Fentanyl Stay in Your System

What kind of drug test you take plays a key role in how long fentanyl will be detectable, but it does not affect how long the drug actually stays in your system. After fentanyl’s brain effects wear off, your body continues to break down the substance and remove it.

How long it lasts in your body depends on a number of factors:

Physical Factors

Every fentanyl user’s body is different. How long a person takes to remove all the fentanyl from their system depends on:

  • Metabolism
  • Body fat percentage
  • Overall weight
  • Height
  • Age
  • Overall health
  • Genetic factors

People who are younger, have faster metabolisms, and are fairly healthy will move fentanyl through their system faster than others. The liver and kidneys play a key role in removing toxins from the body.

Fentanyl Use Specifics

Fentanyl is being mixed with heroin and other drugs on the street, leading to more overdoses and making it unclear how much fentanyl a person is taking. How severe a person’s abuse has been plays a huge role in their body’s ability to quickly remove drugs.

Though it might be difficult to gauge how much fentanyl an addict has been taking, it is an important factor. People who are taking large doses, with a high frequency of use for a long duration of time are going to have a build-up of fentanyl in their bodies.

This means that when they begin detoxing from the drug, it will take them longer than someone who has only used fentanyl a few times.

Mental Factors

Good physical health is not the only thing that can make detox faster. Mental conditions like anxiety and depression can slow down the body’s ability to break down fentanyl. Therefore, those who have good mental health should be able to get clean faster.

Treatment For Fentanyl Addiction

Fentanyl abuse is no joke. Thousands of people are dying every year because of this potent killer. If you or someone you know has been using fentanyl in any way other than as prescribed by a doctor, you need to get help.

Call your local treatment center today to get started on the path to recovery.

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