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Fentanyl Warnings & Side Effects

Published on November 24, 2020
gloved person holding a small bag of white fentanyl powder

Some health care professionals prescribe fentanyl to treat cancer pain, severe chronic pain, or pain following surgery. 

As an opioid analgesic (pain reliever), fentanyl alters the way the brain and central nervous system react to pain. 

It comes in multiple forms, including a lozenge (brand name Actiq), nasal spray (brand name Lazanda), transdermal patch (brand name Duragesic), and injection (brand name Sublimaze). 

When taken as prescribed, fentanyl can provide reliable, effective pain relief. However, it can also cause a number of adverse effects.

Fentanyl Warnings

As with many other opioid medications, fentanyl is classified by the United States Food and Drug Administration (FDA) as a Schedule II controlled substance. This means it has a high potential for abuse and addiction. 

People abuse fentanyl to feel euphoric or “high.” Abuse occurs when someone takes fentanyl in a manner not prescribed by their doctor. 

Fentanyl abuse increases your risk of serious health conditions such as:

Head Injury

When you use fentanyl without following your doctor’s instructions, the drug may impair your judgment. With poor judgment, you might engage in risky behaviors that can lead to head injuries, such as driving under the influence.

HIV & Hepatitis C

You can contract HIV as well as Hepatitis C by sharing needles or other drug use equipment. Hepatitis C is an infection that can cause serious liver damage. 

Sleep Apnea

Fentanyl can slow your breathing, especially at high doses. That’s why some people who abuse fentanyl develop sleep apnea, which is a serious sleep disorder that disrupts your ability to breat

Fentanyl Overdose

Overdose can occur when you take a large amount of fentanyl. People who abuse or are addicted to fentanyl face a much higher risk of overdose than people who take it as prescribed.

Signs of fentanyl overdose include:

  • breathing problems, such as shallow breathing or stopped breathing
  • dizziness
  • sleepiness
  • confusion
  • smaller pupils
  • loss of consciousness

Immediately call 911 if you or someone you know experiences these symptoms. A fentanyl overdose may be life-threatening. 

In many cases, first responders will administer naloxone, a medication that can rapidly reverse the effects of an opioid overdose. 

Fentanyl Side Effects

Whether you abuse fentanyl or take it as prescribed, you may experience the drug’s side effects. 

The most common side effects of fentanyl include:

  • drowsiness 
  • strange dreams
  • constipation
  • trouble urinating
  • stomach pain
  • anxiety
  • depression
  • insomnia
  • sedation
  • heartburn
  • vision changes
  • dry mouth
  • redder face, neck, or upper chest
  • uncontrollable shaking of a body part
  • weight loss
  • back pain
  • chest pain

The drug’s rarer side effects include:

  • hallucinations
  • decreased sexual desire and/or ability
  • irregular menstruation 
  • nausea and/or vomiting
  • diarrhea
  • loss of appetite
  • hives, rash, and/or itching
  • impaired coordination
  • fever
  • increased heart rate 
  • muscle stiffness or twitching
  • seizures

If you experience any of these side effects, contact your health care provider.

Finally, the drug’s most serious side effects include:

  • extreme drowsiness
  • dizziness
  • confusion 
  • trouble breathing or swallowing 
  • slow, shallow breathing
  • fainting
  • serotonin syndrome

Immediately contact your health care provider or call for emergency medical services if you experience these serious side effects. 

Fentanyl Addiction Treatment Options

If you or someone you love struggles with fentanyl abuse or addiction, it’s important to seek medical advice at a drug abuse treatment center. 

Most people who are addicted to fentanyl or other opioid medications will require medication-assisted treatment (MAT).

In MAT, your treatment team can make your recovery quicker and easier by prescribing medications like buprenorphine that help treat opiod addiction. 

As you take your medications, you’ll have access to other recovery services that help you recover from opioid drugs and prescription drugs.

To learn more about treatment options for fentanyl addiction, please contact an Ark Behavioral Health specialist today.

Written by Ark Behavioral Health Editorial Team
This page does not provide medical advice.

Journal of Anaesthesiology, Clinical - A Systematic Review of the Effects of Sedatives and Anesthetics in Patients with Obstructive Sleep Apnea
National Institute on Drug Abuse - Drug Use and Viral Infections (HIV, Hepatitis) DrugFacts
U.S. Food and Drug Administration (FDA) - CFR - Code of Federal Regulations Title 21
U.S. National Library of Medicine: MedlinePlus - Fentanyl

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