Fentanyl Side Effects & Warnings

Manish Mishra, MBBS

Medically Reviewed By: Manish Mishra, MBBS

on December 10, 2022

Fentanyl (known under the brand names Actiq, Duragesic, and Sublimaze) is a highly addictive synthetic opioid used for the short-term relief of chronic pain. It can come as a pill, a lozenge, or a transdermal fentanyl patch. It’s also sold illegally as a nasal spray, powder, and on blotter paper.

The Drug Enforcement Administration (DEA) and Food and Drug Administration (FDA) classify it as a Schedule 2 controlled substance. This means that it may have some medical uses but it also has a high potential for abuse and can lead to physical dependence and addiction.

On top of how addictive fentanyl can be, the prescription drug also comes with a number of side effects and a wide array of warnings about what drugs it negatively interacts with and the ways it can increase the risk of overdose death.

Side Effects Of Fentanyl

Fentanyl comes with a variety of side effects that range from mild to severe. If you’re abusing or misusing the drug, these adverse effects can be even more intense and severe.

Common Side Effects

The most common side effects of fentanyl use can include:

  • drowsiness
  • heartburn
  • weight loss
  • difficulty urinating
  • changes in vision
  • anxiety
  • depression
  • difficulty falling/staying asleep
  • uncontrollable shaking
  • nausea and vomiting
  • dizziness
  • constipation
  • diarrhea
  • loss of appetite

Serious Side Effects

Some of the serious side effects that may occur when taking or abusing fentanyl include:

  • shallow breathing, respiratory depression, or other breathing problems
  • fainting
  • severe dizziness
  • confusion
  • chest pain
  • severely low blood pressure
  • increased blood pressure
  • fast breathing rate
  • fast heart rate
  • severe tiredness
  • muscle weakness
  • abdominal pain

Fentanyl Warnings

Fentanyl also comes with warnings about drug interactions, the potential for abuse and addiction, and the risk of fentanyl overdose.

These warnings can often be ignored when someone is dealing with severe pain, addiction, or intense cravings. Unfortunately, ignoring these warnings can lead to serious, life-threatening issues.

Drug Interactions

There are several drugs that don’t interact well with fentanyl. Combining fentanyl with any of the following substances can lead to serious reactions:

  • alcohol
  • benzodiazepines
  • other opioid painkillers
  • certain over-the-counter supplements
  • ketoconazole
  • phenytoin (Dilantin)
  • carbamazepine (Tegretol)
  • rifampin (Rifadin) 
  • sedative-hypnotics such as zolpidem, temazepam, and estazolam
  • antihistamines
  • barbiturates
  • muscle relaxants

For those breastfeeding, fentanyl can transfer to breast milk and can cause side effects like sedation. It’s important to talk to your doctor before breastfeeding while on fentanyl.

Additionally, if you are allergic to any of the ingredients in fentanyl, an allergic reaction will likely show up as a rash, itching, trouble breathing, trouble swallowing, or swelling of your hands, face, or mouth.

Fentanyl Overdose

Misusing and abusing fentanyl can also put you at a higher risk for an overdose. A fentanyl overdose can be fatal if left untreated. If you or a loved one is experiencing any of the following symptoms, call 911 immediately:

  • not responding to sound or touch
  • trouble breathing
  • sleepiness
  • muscle weakness
  • small pupils
  • cold or clammy skin
  • low blood pressure
  • slow heart rate
  • coma

If there is Narcan or naloxone available, now is the time to administer that. It will give emergency help more time to get to you.

Opioid Addiction

Opioid use disorder can quickly develop after a period of fentanyl use. This mental health condition is characterized by an inability to stop using opioid drugs despite harmful consequences in a person’s life.

If you take high doses of fentanyl and suffer from addiction, you have an increased risk of experiencing withdrawal symptoms once you stop use.

Opioid Addiction Treatment

If you do choose to stop taking fentanyl, the help and supervision of a healthcare professional is recommended. They will likely put you in a detox program where they monitor your withdrawal symptoms and prepare you for outpatient or inpatient addiction treatment.

Opioid addiction treatment options include services like behavioral therapy, peer support groups, and medication-assisted treatment with methadone, buprenorphine, and naltrexone.

If you or a loved one is struggling with fentanyl addiction and looking for treatment, please contact Ohio Recovery Center today.

  1. Centers for Disease Control & Prevention (CDC) — Fentanyl Facts https://www.cdc.gov/stopoverdose/fentanyl/index.html
  2. Mayo Clinic — Fentanyl (Transdermal Route) https://www.mayoclinic.org/drugs-supplements/fentanyl-transdermal-route/precautions/drg-20068152
  3. National Institute on Drug Abuse — Fentanyl DrugFacts https://nida.nih.gov/publications/drugfacts/fentanyl
  4. National Library of Medicine: MedlinePlus — Fentanyl https://medlineplus.gov/druginfo/meds/a605043.html
  5. ational Library of Medicine: StatPearls — Fentanyl https://www.ncbi.nlm.nih.gov/books/NBK459275/

Written by Ohio Recovery Center Editorial Team

© 2024 Ohio Recovery Center | All Rights Reserved

* This page does not provide medical advice.

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