Substance Use

How Long Does Fentanyl Stay in Your System?

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Fentanyl is a powerful synthetic opioid. It is similar to morphine but 50-100 times more potent. Although fentanyl is a prescription drug with legitimate medical uses, this drug is also being made, distributed, and used illegally.

It takes very little fentanyl to produce a high, making it cheaper for the dealer. Sadly, the dose is often too strong for an unexpected user, increasing the likelihood of an overdose. Users either take too much fentanyl without realizing the dosage or face an overdose after taking a laced drug. 

Learn more about fentanyl addiction, how long fentanyl stays in your system, and how to get help for opioid addiction today.

How Long Does Fentanyl Stay in Your System?

The duration of fentanyl in your system varies depending on the type of test that is used. Urine tests can typically detect fentanyl within 24-72 hours after the last use. Hair tests have a longer detection window of up to 3 months. Blood tests can detect fentanyl between 5 and 48 hours of the last use, with the detection time affected by the dosage administered.

Data shows that how often fentanyl is used affects how long the drug remains in your system. For example, after one or a few doses, fentanyl is cleared from the body after 2–4 days. However, with regular use, fentanyl will become stored in fat tissue. This prolongs clearance. When testing the urine of twelve regular fentanyl users in a 28-day residential program it was found that:

  • The average time for fentanyl to leave their system was seven days, yet 13 days for fentanyl’s metabolite, norfentanyl 
  • One individual tested positive for fentanyl for 19 days after last use and 26 days for norfentanyl 

How Long Does It Take for the Effects of Fentanyl to Wear Off?

Much like morphine and heroin, fentanyl works by binding to opioid receptors, which are found in brain areas that influence emotions and pain. This leads to effects that are similar to morphine, including:

  • Pain relief 
  • Euphoria 
  • Relaxation 
  • Confusion 
  • Sedation 
  • Nausea and vomiting 
  • Drowsiness 

These effects can quickly turn to signs of overdose, including stupor, respiratory failure, blue-colored skin, cold skin, changes in pupil size, and coma. 

How long the effects of fentanyl last depend on several factors, particularly how the drug is administered and the dosage. Other variables include your weight and overall health, your tolerance level, and whether or not fentanyl is taken with other substances. 

These variables also affect how quickly the effects of fentanyl are experienced. For example, if a user administers fentanyl intravenously, the effects are often immediate. Some users will pass out with the needle still in their arm. However, the peak respiratory depressant and analgesic effect may take several minutes. When taking 100 mcg intravenously (which is equivalent to approximately 10 mg of morphine), the effects typically last 30 to 60 minutes

When taking fentanyl via intramuscular administration, the onset of action is approximately 7-8 minutes, with the effects lasting around two hours. 

If you’re taking a patch, the effects may take up to 45 minutes to kick in. Smoking or snorting illicit fentanyl is also very dangerous, being powerful enough to cause an overdose. When smoking, for example, it is difficult to control the dose.

When smoking, snorting, or injecting fentanyl, the effects last up to 90 minutes. In contrast, when slowly released via a patch, the effects can last up to 72 hours

Are you concerned for your loved one? Are you ready to seek a life of sobriety? Learn more about the substance use services offered by Zinnia Health facilities. 

How Is Fentanyl Detected on Drug Tests?

There are several reasons why you may be tested for the presence of fentanyl. In a medical setting, if a user is being treated for a potential overdose, blood work will help determine what substances are in a patient’s system. In other settings, such as a treatment center, urine testing is most common. This is because urine is easy to collect, provides adequate sensitivity, and has a longer detection window than serum (which is associated with blood work). 

Saliva, sweat, and hair can also be tested. However, these methods are not common. 

Urine testing typically involves two steps — an initial screening test, followed by confirmatory testing for positive screening results. Initial screening is most often an immunoassay test that screens for five major drug classes. These include cannabinoids, opioids, cocaine, phencyclidine, and amphetamines. 

When testing specifically for fentanyl, fentanyl test strips will be required. These tests can be used pre-consumption to test drugs or after consumption via a urine test (within approximately three days of consumption). These strips can detect fentanyl with a high level of accuracy

To study whether the metabolites of fentanyl would be useful when aiming to monitor and detect substance abuse, urine and saliva samples were tested from seven female patients. These women received small doses of fentanyl (110 +/- 56 micrograms) and were studied up to 96 hours from the time of administration. 

Results showed that unchanged fentanyl was detected in all patients immediately following surgery and in 3 out of 7 patients at 24 hours. By 72 hours, fentanyl could not be detected. However, its metabolite, norfentanyl, was detected in all patients at 48 hours and in 4 out of 7 patients at 96 hours — in urine only. It was concluded that saliva testing is not a viable testing option compared to saliva.

There are also tests that help users take a proactive approach against a potential overdose. In response to the current opioid pandemic, and the rising cases of overdoses related to fentanyl, the CDC announced that federal grantees may now use funding to purchase fentanyl test strips. These test strips can be used to determine whether drugs have been cut or mixed with fentanyl.

This initiative was launched when the number of overdose deaths in the U.S. reached 88,000 in the 12 months ending in August 2020. This increase in overdose deaths has been linked to synthetic opioids, including fentanyl. By 2021, overdose rates were even higher. From January 2020 to January 2021, overdose deaths involving synthetic opioids (primarily illicitly manufactured fentanyl) rose by 55.6%.

Data shows that rates of the combination of fentanyl and cocaine or methamphetamine have increased in urine tests across time. This is providing insight into reported increases in cocaine- and methamphetamine-related overdoses. 

How Is Fentanyl Metabolized in the Body?

Fentanyl is broken down and eliminated almost exclusively by the liver. However, among opioids that undergo CYP-mediated metabolism (CYPs are a specific family of enzymes), fentanyl and methadone are less affected by liver disease, as well as kidney issues. That is often why these are the drugs recommended during end-stage renal disease. 

Fentanyl breaks down into several metabolites, including norfentanyl and despropionylfentanyl. Approximately 99% of fentanyl is metabolized to norfentanyl.

The CYP3A4 enzyme is the primary metabolizer, which is what turns fentanyl into norfentanyl. This metabolite is present in high levels compared to other metabolites and is both inactive and nontoxic. 

To better understand how the body metabolizes fentanyl, you could also consider the drug’s half-life. This is the amount of time required to reduce fentanyl’s active substances in the body by half. Fentanyl’s half-life is 8-10 hours, which means that following this period, half the fentanyl in your system would already be eliminated. 

Exercising, drinking plenty of water, and other myths surrounding the elimination of fentanyl will not clear this drug from your body any quicker. The only way to remove fentanyl from your system is to allow your body to fully metabolize and eliminate it. 

How Zinnia Health Provides Support for Fentanyl Addiction

As reported by the DEA, two milligrams of fentanyl can be lethal. The DEA has found fentanyl pills that range from .02 to 5.1 milligrams (over twice the lethal dose) per tablet. Shockingly, 42% of pills tests contained at least two mg of fentanyl — a potentially fatal dose. A user cannot tell them how potent one of these tablets is. In comparison, a high dose in a medical setting would be between 0.02 and 0.05 mg, which would be administered for open-heart surgery. 

In a 2021 report, the DEA stated that during an eight-week period, they targeted the criminal networks flooding the United States. The fentanyl-laced fake pills they seized could potentially kill over 700,000 Americans. The number of pills that contain fentanyl has increased by nearly 430% since 2019 — and these fake pills are becoming more potent and lethal than ever before. 

When prescribed by a doctor, fentanyl can be given as a shot, as a patch, or as lozenges, all of which are closely monitored and administered with care. When used illegally, fentanyl is made in labs and sold as pills, powder, or even nasal sprays. Unfortunately, this drug has led to a significant increase in overdoses. In many cases, this is because dealers are mixing fentanyl with other drugs, including MDMA, cocaine, and heroin. 

Fentanyl has a high potential for abuse because of its potency. Even when fentanyl is prescribed by a doctor and is taken according to the instructions provided, you can still experience dependence, which results in withdrawal symptoms with discontinued use. 

If fentanyl has become an issue in your life, you must seek help as soon as possible. Fentanyl is deadly. A single dose can take your life. 

Withdrawal symptoms can be severe, ranging from muscle and bone pain to vomiting, sleep issues to uncontrollable leg movements. These effects are incredibly uncomfortable and are why people continue using fentanyl. Medical detox can significantly assist with this process, increasing your chances of success. 

At Zinnia Health, we help you get to a detox treatment center to address your physical dependence. That is step one. Once your body has eliminated the drug, you can then begin the healing process. For some, this means addressing trauma, while others highly benefit from family therapy following the aftermath of addiction. 

To increase your chances of a successful recovery, it’s important to seek a treatment program that is tailored to you and your individualized history, needs, and goals. At Zinnia Health, we understand how important a customized approach is during recovery. That is why we offer such a wide spectrum of treatment options at our expert facilities, as well as extra amenities to ensure a comfortable stay. 

For example, by offering unique amenities such as a professional recording studio, a dedicated meditation space, a full library, and an extensive gym, individuals can heal and find purpose. Taking the time to do things that are fulfilling and rewarding can help guide you towards a healthier, happier future. 

Throughout treatment, several therapy options are provided, focusing on evidence-based treatments. From experiential therapy to acceptance and commitment therapy, we offer all treatment methods as part of a residential inpatient program, an intensive outpatient program, or a partial hospitalization program. 

If you or your loved one are ready to take the next step to protect your health and, ultimately, your life, Zinnia Health is here to help. Contact us to discuss your unique needs so that we can create a customized program for you today.

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