Fentanyl Addiction: Side Effects, Detox, & Rehab

Fentanyl is a powerful synthetic (manmade) opioid with a high addiction potential. It’s associated with many serious health risks, including fatal overdose. In 2019, synthetic opioids (mostly fentanyl) were involved in over 36,359 fatal overdoses in the United States, comprising 51% of the total overdose deaths.1 This page will discuss the effects of fentanyl, the risks of misuse, and treatment options for fentanyl addiction.
About Fentanyl

What is Fentanyl?

Fentanyl is a highly potent synthetic opioid used to treat severe pain, often following major surgery. It may also be prescribed to patients suffering from chronic pain, specifically cancer-related pain, if they have become tolerant to other opioids (meaning they need more or increasingly higher doses of other opioids to relieve their pain). The high potency of fentanyl makes it particularly dangerous, especially in terms of addiction and overdose.2

Because it has recognized medical benefits but a high potential for abuse, fentanyl is classified as a Schedule II substance by the Drug Enforcement Administration (DEA).3 Prescription fentanyl is often sold in the form of oral tablets, lozenges, shots, or transdermal patches.

Brand names of fentanyl include:2, 4

  • Actiq.
  • Fentora.
  • Duragesic.
  • Sublimaze.

While fentanyl is considered a prescription opioid, much of the fentanyl that is sold on the street in the United States was manufactured illegally.5 It’s common for other drugs (e.g., heroin, cocaine, counterfeit prescription pills, and others) to be mixed with fentanyl unknown the person using them.2

Fentanyl can be smoked, snorted, or injected intravenously.2

Common street names for fentanyl include:5

  • Apace.
  • Tango and cash.
  • He-Man.
  • Dance fever.
  • Poison.

Is Fentanyl Addictive?

Fentanyl, like other opioids (e.g., heroin, OxyContin, morphine, etc.) is considered highly addictive.6

Fentanyl addiction or opioid use disorder is a chronic medical condition that affects the brain and body. It occurs when an individual cannot cut back their fentanyl intake or quit using despite the negative consequences on their lives and others around them.6

Opioid use disorder affects every aspect of an individual’s life, including social life, personal life, and professional life. It can often result in legal troubles, broken relationships, job loss, financial hardships, and emotional and mental turmoil.6

Fentanyl can also cause someone to form dependence quickly. Fentanyl dependency occurs when the body and brain re-wire its chemistry to adjust to the drug of abuse. The individual will likely experience withdrawal symptoms when they cease or reduce their intake after using the drug for a prolonged period. Although dependence and addiction are very different, often when an individual is addicted to fentanyl, they have a high likelihood of also being dependent on fentanyl.6

Additionally, the subjective effects of fentanyl reinforce and reward compulsive use. Continued fentanyl use also causes someone to build a tolerance rapidly, causing them to need more of the drug to feel the same effects.6

Researchers believe that repeated use of opioids or other drugs of abuse can alter the structure of the brain over time, which may explain why some people relapse even after they’ve been sober for a long time.7

There are also many other factors other than a drug itself that may influence someone to struggle with addiction. These include, but are not limited to:8

  • Genetics.
  • Using drugs or drinking alcohol at a young age.
  • The presence of co-occurring disorders. Approximately half the people that suffer from substance use disorder (SUD) also have other mental health disorders and vice versa.
  • Experiencing trauma.
  • High levels of stress.
Effects & Risks of Fentanyl

Immediate Effects of Fentanyl Use

Fentanyl produces similar immediate effects to other opioids like heroin and morphine. The immediate effects of fentanyl include:2, 4, 5

  • Euphoria.
  • Relaxation.
  • Drowsiness.
  • Dry mouth.
  • Tremors.
  • Itching.
  • Constipation.
  • Confusion.
  • Slowed heartrate and respiration.
  • Overdose.

Just a small amount of fentanyl can cause a fatal overdose—the drug is an estimated 50-100 times stronger than morphine.2

Risks of Mixing Fentanyl with Other Drugs

Mixing fentanyl with other drugs is extremely risky. This practice can put an individual in danger of suffering the health consequences of either drug separately, as well as added risks unique to the combination of certain substances.

Opioids and stimulants used simultaneously—such as cocaine and fentanyl—can impair the ability of someone to control and coordinate motor skills and increase the risk of serious complications, like heart attack, stroke, brain aneurysm.11

Using benzodiazepines (e.g., Xanax, Valium) and opioids at the same time puts an individual at a heightened risk of overdose, since both drugs depress respiration and the central nervous system. The risk was serious enough for the Centers of Disease Control and Prevention (CDC) to warn clinicians to avoid prescribing opioids and benzodiazepines simultaneously. In 2019, 16% of opioid overdoses involved a benzodiazepine.12

Drinking alcohol while under the effects of fentanyl is also highly dangerous because of the way both alcohol and opioids slow breathing and heartrate, causing potential loss of consciousness, coma, and death.13

Unfortunately, many people that misuse fentanyl do so unknowingly. The drug is cheap to produce, prompting illicit manufacturers and drug dealers to disguise less potent products (even stimulants or counterfeit prescription drugs) by cutting them with fentanyl. This practice has caused many accidental overdoses.2, 5

Signs of Fentanyl Addiction

What Are the Signs of Fentanyl Addiction?

Fentanyl addiction—also called opioid use disorder (OUD)—is a condition that should be diagnosed by a medical professional. Specialists use the criteria outlined in the Diagnostic and Statistic Manual of Mental Disorders (DSM-5) to diagnose someone with OUD. If 2 or more of the following criteria are met within a year, they may be diagnosed with an addiction to fentanyl.14

How to Recognize a Fentanyl Overdose

A fentanyl overdose is extremely dangerous and requires immediate medical attention. Symptoms of a fentanyl overdose include:4, 15

  • Drowsiness, dizziness, or confusion.
  • Slowed, shallow breathing, or breathing may cease completely.
  • Pinpoint pupils.
  • Unresponsiveness or inability to wake up.
  • Making choking or gurgling sounds.

Bystanders should immediately contact emergency services and administer naloxone to someone experiencing an opioid overdose. In New Jersey and many other states, naloxone is legal to obtain and carry without a prescription.16

Because fentanyl is so powerful, it may take multiple doses of naloxone (spaced 2-3 minutes apart) to reverse an overdose. If possible, the person suffering the overdose should be turned on their side to prevent vomit from getting stuck in their airway, and a witness should stay with them until emergency services arrive.2

Fentanyl Addiction Treatment

Fentanyl Withdrawal & Detox

Opioid withdrawal—while seldom life-threatening—can be incredibly unpleasant. In many cases, the symptoms of fentanyl withdrawal can cause someone to relapse just to escape the discomfort. Medical detox is often a necessary step for many people to get over the initial hurdle of acute withdrawal.17

Symptoms of Fentanyl Withdrawal

Fentanyl withdrawal may begin as early as several hours after someone takes their last dose. Common fentanyl withdrawal symptoms include:2

  • Aching bones and muscles.
  • Stomach cramps.
  • Cold flashes.
  • Leg spasms.
  • Diarrhea.
  • Vomiting.

Fentanyl is a short-acting opioid, which means withdrawal typically lasts 3 to 5 days.17, 18

Fentanyl Addiction Treatment & Rehab Options

As mentioned above, the first step in opioid addiction treatment is usually medical detox. Medical detox enables the patient to withdraw safely while monitored by nurses and specialists 24/7 who can administer medications to ease symptoms and respond to emergencies if necessary.

Special opioid agonists (e.g., methadone or buprenorphine) that do not elicit a high in opioid-tolerant people are often administered in detox to ease symptoms and cravings.15 This practice often continues in tapering doses for months or even years into someone’s recovery.19, 20

These drugs—when used correctly—enable someone recovering from opioid use disorder (OUD) to work a job, attend school, have a social life, and otherwise participate in society.19, 20

Other drugs are sometimes used during detox to treat withdrawal symptoms in lieu of opioid agonists. Clonidine and lofexidine are common non-opioid agonists prescribed for opioid withdrawal.19, 20

Following detox, it’s important that patients build the skills necessary to stay in long-term recovery.7, 17 Various forms of therapy during rehab help patients to identify and overcome the obstacles that make them want to use drugs, form and mend positive interpersonal relationships, repair positive thought and behavioral patterns, and more.21

Recovery is a life-long process, and it’s crucial for people to remain motivated, focused, and surrounded by a positive network of supportive peers to be stay sober. Aftercare, which includes anything from transitional housing (sober living) to attending weekly 12-step group meetings provides a solid support system for many people after they complete rehabilitation at an addiction treatment facility.22

If you or a loved one is struggling with fentanyl addiction, it’s not too late to get help. Please reach out to an admissions navigator at to learn about the care provided at Sunrise House Treatment Center.

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