Fentanyl Abuse: Short- and Long-Term Health Effects

If you or your loved one is struggling with fentanyl abuse or with using other opioids, you should be aware of the immediate and long-term side effects and other health issues they can cause. This page will discuss these short- and long-term health effects and cover the options you have for treating fentanyl addiction and opioid use disorder.

What Are the Short-Term and Immediate Side Effects of Fentanyl Abuse?

Tube of fentanyl

When a person uses fentanyl, a powerful opioid painkiller, they will experience its pain-relieving and euphoric effects almost immediately. Like any medication there are also side effects. Potential short-term side effects of fentanyl include:1,2

  • Drowsiness.
  • Confusion.
  • Small pupils.
  • Constipation.
  • Nausea.
  • Vomiting.
  • Slowed breathing.

Fentanyl Overdose Risk

Whenever a person takes fentanyl, there is a risk of overdose. Fentanyl is a very powerful opioid (about 50x more potent than heroin). It and other similar synthetic opioids were involved in the overdose deaths of more than 36,000 people in 2019 in the United States. Fentanyl and other illicitly manufactured synthetic opioids that are similar to fentanyl and increasingly being found in other street drugs, such as heroin, cocaine, MDMA, meth and counterfeit pills (e.g., Xanax, OxyContin).3

The risk of overdose is increased when people take fentanyl illicitly, especially if it is mixed with other drugs, but an overdose can happen even when fentanyl is taken as prescribed by a doctor. This is especially true for people over the age of 65 or those who have certain illnesses, such as sleep apnea or disease of the liver or kidneys. People who combine fentanyl with alcohol or other drugs, particularly other opioids or benzodiazepines, or take more than was prescribed are also at increased risk of overdosing.4

A fentanyl overdose may be deadly. If you recognize the following signs of overdose, call 911 right away:4

  • Tiny pupils.
  • Loss of consciousness.
  • Shallow, irregular, or stopped breathing.
  • Limp body.
  • Blue, cold, or pale skin.
  • Choking or gurgling noises.

After calling 911, you can:4,5

  • Administer naloxone (Narcan, Kloxxado) if you have some.
    • If the person doesn’t begin breathing normally within 2-3 minutes, administer another dose.
  • Try to keep the person conscious and awake.
  • Place the individual in the recovery position by holding the far leg just above the knee to pull it up, then rolling the person toward you so they are positioned on their side. Their hand should be placed under their head, which will help prevent choking if they vomit.
  • Stay with the person until help arrives.

What Are the Long-Term Effects of Fentanyl?

Long-term use of fentanyl or other opioids may increase the risk of:6

  • Fractures in the elderly.
  • Chronic and severe constipation, which may lead to serious health problems such as bowel obstruction.
  • Breathing problems during sleep.
  • Heart attack and heart failure.
  • Immune system suppression.
  • Hormonal and reproductive issues in both men and women.
  • Anxiety, depression, and other mood disorders.

A person who takes fentanyl or other opioids long-term will become increasingly tolerant to their effects, which means they will need to up their dosage or how often they take it to feel its effects. Developing a tolerance to fentanyl or other opioids increases the risk of opioid dependence. People who have become dependent on opioids will experience withdrawal if they stop using them.2

Tolerance and dependence can occur even with therapeutic use of opioids.  They can, however, both lead to compulsive drug-seeking and can be precursors to and signs of addiction.  An opioid use disorder—the diagnostic term for opioid addiction—is characterized by uncontrollable drug use despite the significant negative consequences that result from it.7

Along with tolerance and dependence/withdrawal, signs of an opioid use disorder include:7

  • Taking more opioids or taking them for longer than you intended.
  • Taking fentanyl or other opioids despite knowing it makes emotional or physical problems worse.
  • Using opioids in high-risk situations, such as driving.
  • Failing to meet responsibilities at home, school, or work due to fentanyl or other opioid use.
  • Experiencing relationship problems due to your opioid use.
  • Spending a great deal of time acquiring, using, and recovering from fentanyl or other opioids.
  • Giving up previously important hobbies or leisure pursuits to use opioids.
  • Trying to stop using opioids and being unable to do so.
  • Experiencing opioid cravings.

Fentanyl Addiction Treatment and Recovery

If you are abusing opioids such as heroin and fentanyl, the sooner you quit using, the better chance you have at preventing serious long-term side effects or experiencing a potentially deadly overdose. There are several options for treatment programs that can help with fentanyl misuse:8,9

  • Medical detox, which enables you to get through opioid withdrawal in a safe and comfortable environment where you can get help managing your acute symptoms and drug cravings.
  • Inpatient treatment, where you receive treatment 24/7. The duration of an inpatient stay varies depending on individual factors such as your substance use history, prior attempts at rehab, , etc. If you have co-occurring medical or mental health conditions or issues with polysubstance use inpatient treatment may be a good option for you.
  • Outpatient treatment, which is offered in several forms. Day treatment, or partial hospitalization, is the most intensive with treatment around 4-6 hours per day, 5 days per week. Intensive outpatient involves about 2-3 hours of treatment per day at least 2 days per week. Standard outpatient treatment is the lowest level of outpatient care and generally involves only 1-2 sessions per week. This form is often a part of an aftercare plan for people who have completed a more intensive type of treatment.

Holding hands

Some treatment programs use medication-assisted treatment (MAT). This involves the use of medications in addition to behavioral therapies to provide a well-rounded treatment approach.10 The most common types of medications used in the treatment of fentanyl or other opioid addiction include:11-13

  • Methadone, a full opioid agonist medication that alleviates cravings and withdrawal symptoms without eliciting a euphoric high. This medication may only be given in opioid treatment programs and certain inpatient settings.
  • Buprenorphine, a partial opioid agonist with a ceiling effect to lower misuse and overdose risk. Buprenorphine helps manage withdrawal, minimize drug cravings, and can be prescribed on a long-term basis to help people maintain recovery and avoid relapse. Suboxone, a common buprenorphine-based medication, contains naloxone to prevent abuse by injection.
  • Naltrexone, which binds to and blocks opioid receptors, eliminating the potential for getting from high from using opioids.

Don’t let addiction take control of your life any longer. Call us today at to learn more about addiction treatment at AdCare. There are two inpatient AdCare facilities, one inpatient Rhode Island rehab, and one inpatient rehab in Massachusetts. AdCare also offers outpatient treatment and has sister facilities across the United States as well. Call us today to learn more about our comprehensive addiction treatment options.

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