What To Expect During Fentanyl Withdrawal

Nearly 100 times more potent than morphine, fentanyl is one of the most addictive and deadly drugs in the world. Due to this high potency, fentanyl affects the body and brain in multiple ways and can quickly lead to physical dependence and addiction. Because addiction can occur rapidly with fentanyl abuse, withdrawal can be challenging.

For any psychoactive substance, like fentanyl, the likelihood of withdrawal depends on two factors: how frequently someone uses a substance and how much of that substance they typically use at one time.

For example, someone who uses fentanyl in what are known as “binges,” using fentanyl in short periods followed by long periods of absence, is less likely to experience significant withdrawal symptoms since their brain hasn’t become dependent on fentanyl. On the other hand, someone who uses fentanyl daily is much more likely to have withdrawal symptoms that are more severe, particularly if they have been using larger amounts.

Fentanyl Withdrawal Timeline

For opioids like fentanyl, withdrawal symptoms typically develop when someone has been using the drug for several weeks or longer, although someone with a history of heavy prolonged opioid use can experience withdrawal symptoms after shorter periods.

Withdrawal symptoms may be triggered by someone significantly reducing the amount they have been using or stopping “cold turkey.” For this reason, many people try to taper themselves by gradually reducing the amount of the substance to avoid withdrawal symptoms.

The timeline for when withdrawal symptoms start depends on the half-life of the drug, which refers to how quickly the drug is metabolized by the body. Withdrawal symptoms for drugs with a short half-life can start within hours of the last use of the substance. The onset of withdrawal also depends on the method of administration, which is how someone gets the substance into their body. The slowest method of administration is transdermal (absorbing the drug through the skin), and the fastest is smoking.

Some opioids, like heroin, are relatively short-acting, with a half-life of about 8 minutes, and the withdrawal symptoms can start within minutes of missing a dose the body has learned to expect. Oxycodone is longer-lasting, with a half-life of around 5 hours, and the longest-acting opioid is methadone, with a half-life of 23 hours.

Pharmaceutical fentanyl has a half-life of 3-4 hours, but illicit fentanyl can have a longer half-life. Recent trends of combining fentanyl with the animal tranquilizer xylazine reportedly extend the length of a fentanyl high, and that combination is linked to a significant risk for overdose and other serious physical effects.    

Symptoms Of Fentanyl Withdrawal

Withdrawal from fentanyl is similar to withdrawal from other opioids. Withdrawal symptoms from any psychoactive substance are essentially the opposite of the drug’s effects. Since fentanyl is a depressant, also called a “downer,” withdrawal symptoms are usually stimulating. As with most substances, fentanyl withdrawal typically has both physical and psychological components.

Psychologically, people who stop using fentanyl are likely to experience:

  • Emotional reactions that could include depression, anxiety, agitation, and irritability.
  • Cravings and obsessive thoughts about drug use.
  • Behavioral reactions that could include restlessness, isolation, and difficulty sleeping.

Physical symptoms of fentanyl withdrawal can include:

  • Fast heart rate
  • Fever, sweating, chills
  • Stomach cramps, nausea, vomiting, diarrhea
  • Runny nose
  • Muscle aches
  • Yawning
  • Dilated (enlarged) pupils

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Medically Supervised Detox Options For Fentanyl Withdrawal

While fentanyl withdrawal can be extremely uncomfortable, it is generally not life-threatening unless the person has underlying health conditions. Like other opioids, fentanyl withdrawal can feel like the seasonal flu and stomach flu at the same time, and the greatest risk is usually that the person can’t tolerate that level of distress and starts using again to combat the withdrawal discomfort.

There are several options for fentanyl detox that can reduce discomfort. Methadone and buprenorphine (Suboxone™) can alleviate withdrawal symptoms and may be an important tool for recovery. For people who don’t want to start those medications, other prescription medications can reduce some of the withdrawal symptoms, often called “comfort meds.”

The most common detox programs are medically-supervised inpatient, or residential, programs where the person stays overnight for 2 – 5 days. During that time, their vital signs and symptoms are monitored, they are fed and hydrated, and they receive medications to reduce the physical and emotional discomfort of withdrawal. Detox programs like these are often the first step toward longer-term addiction treatment, and staff in detox programs will offer assistance in selecting and finding the most appropriate next step in treatment.

Although they are less common, outpatient detox protocols are administered by physicians and psychiatrists with specialized training in addiction. They typically involve assessment, periodic monitoring, and prescription medications to take at home to reduce physical and emotional discomfort. The most common type of outpatient detox is medication-assisted treatment (MAT), which involves starting the person on methadone or buprenorphine to combat withdrawal symptoms and help the person establish abstinence from opioids like fentanyl.

Find Help For Fentanyl Detox Today

While fentanyl detox is not usually life-threatening, it can be extremely difficult to manage without medical support. The symptoms of withdrawal, without the presence of detox-aid medications, can be severely uncomfortable and may lead many to use fentanyl again to escape them.

Medically supervised detox not only helps alleviate these symptoms but also gives you the greatest chance for a successful recovery. If you or someone you know is struggling with fentanyl abuse and is looking for detox options, contact a treatment provider today to start your recovery journey.