Last published: June 06, 2024

What is fentanyl?

Fentanyl is an opioid.

Opioids are drugs that act on the opioid receptors in the brain, they include both natural and synthetic drugs that are derived from, or related to, the opium poppy.

Fentanyl is prescribed for chronic pain, severe cancer pain, nerve damage, back injury, major trauma and surgery.1 In Australia, fentanyl is a Schedule 8 drug.2 It’s about 80 to 100 times stronger than morphine.3

What it looks like

Fentanyl is available in many forms. Pharmaceutical fentanyl is used for managing acute or chronic pain and can come in patches, lollipops, or administered as an injection. Illicit fentanyl can be manufactured for use in the illegal drug market.

Other names

Goodfella, jackpot, murder 8, TNT, Tango and Cash, fentanil, Sublimaze, Actiq, Durogesic, Duragesic

How is fentanyl used?

Medicinal use

Medicinal fentanyl comes in different forms and strengths including:

  • transdermal patches (Durogesic®, APO-fentanyl® and generic versions)
  • lozenges/lollipops (Actiq®)
  • intravenous injection (Sublimaze® B. BRAUN FENTANYL®).

Illicit use

Some people use fentanyl illegally by extracting it from the patch and injecting it. This is very risky as it is extremely hard to judge a dose size.

Fentanyl can be ‘diverted’ meaning that when the medication is prescribed by a medical professional, it’s not used as directed, or is given or sold to a third party.

Prescribed fentanyl can be 'diverted' when individuals:

  • obtain medication without a prescription from another doctor through their profession (e.g. healthcare professionals)
  • use their own prescribed medication recreationally
  • use medication prescribed for another person.

Fentanyl is sometimes mixed with other drugs to increase its potency. Illicitly manufactured fentanyl can be:

  • a stand-alone product
  • a low-cost additive to increase the potency of other illicit drugs such as heroin
  • sold as counterfeit medicines (such as oxycodone®).

Effects of fentanyl

Use of any drug can have risks. It’s important to be careful when taking any type of drug.

Fentanyl affects everyone differently, based on:

  • size, weight and health
  • whether the person is used to taking it
  • whether other drugs are taken around the same time
  • the amount taken
  • the strength of the drug (varies between drug form e.g. patches, lozenges or injection).

Its effects may include:

  • euphoria
  • relief from pain
  • nausea, vomiting
  • constipation and/or diarrhea
  • reduced appetite
  • wind, indigestion, cramps
  • drowsiness, confusion
  • weakness or fatigue
  • dizziness
  • euphoria
  • headache
  • incoherent or slurred speech
  • impaired balance
  • slow pulse and lowered blood pressure
  • rash (inflammation, itch, swelling at patch site). 1,4


If the dose is too high, you might overdose. Call an ambulance straight away by dialling triple zero (000) if you or someone else has any of these symptoms (ambulance officers do not have to involve the police):

  • chest pain
  • slowed breathing
  • bluish lips and complexion
  • seizure
  • passing out
  • coma
  • death.1,5

In the case of an overdose, Naloxone (also known as Narcan®) reverses the effects of opiates (including fentanyl).

Naloxone, is available over the counter and, is available either as a fast-acting nasal spray or a preloaded multiple dose syringe.

It can be administered by health professionals, family or household members and peers.6 Speak with your chemist or pharmacist for more information.

If injecting drugs, there is an increased risk of:

  • tetanus.
  • infection.
  • vein damage.

If sharing needles, there is an increased risk of:

  • hepatitis B.
  • hepatitis C.
  • HIV and AIDS.

Long-term effects

Regular use of fentanyl may cause:

  • mood instability
  • reduced libido
  • constipation
  • menstrual problems
  • respiratory impairment.3 Tolerance and dependence Using fentanyl on a regular basis can lead to dependence (addiction), and tolerance, which means you need to take larger amounts to get the same effect.

Using fentanyl with other drugs

Mixing fentanyl with other drugs can have unpredictable effects and increase the risk of harm.

  • Fentanyl and amphetamines: can cause heart strain and respiratory arrest.
  • Fentanyl and nitrous oxide: can cause poor muscle control and sedation which can lead to unconsciousness.
  • Fentanyl and alcohol/benzodiazepines/ketamine: can cause sedation, unconsciousness and death. Choking on vomit is a risk.6,7

There is also a risk of serotonin syndrome when mixing fentanyl with some medications such as antidepressants.

More on Polydrug use

Polydrug use is a term for the use of more than one drug or type of drug at the same time or one after another. Polydrug use can involve both illicit drugs and legal substances, such as alcohol and medications.


Reducing harm

  • Always carry naloxone for emergencies, and encourage family and friends to learn how to use take home naloxone – a medicine that can reverse the effects of an opioid overdose (more information on naloxone is provided below).
  • Use in a safe place with people you trust.
  • It's best to start with lower doses due to individual differences between body weight, tolerance and metabolism.
  • If injecting, use new needles and sterile injecting equipment.
  • Avoid taking in combination with alcohol or other drugs, in particular benzodiazepines, or other opioids as these can slow breathing and increase the risk of overdose.
  • Do not drive, swim, or operate machinery.7

If you or someone you know is using fentanyl, talk with your doctor about accessing naloxone, the drug that reverses opioid overdoses. Your friends or family members can be trained in overdose reversal in case of an emergency. For more information


Giving up fentanyl after a long time is challenging because the body has to get used to functioning without it. Please seek advice from a health professional.

Withdrawal symptoms usually start within 12 hours after the last dose and can last for about a week. Days one to three will be the worst. Symptoms include:

  • goose flesh/bumps
  • bouts of chills alternating with bouts of flushing and excessive sweating
  • irritability
  • insomnia
  • loss of appetite
  • yawning and sneezing
  • watery eyes and runny nose
  • vomiting and nausea
  • diarrhea
  • increased heart rate and blood pressure
  • pains in the bones and muscle
  • general weakness
  • depression.3

Getting help

If your use of fentanyl is affecting your health, family, relationships, work, school, financial or other life situations, or you’re concerned about a loved one, you can find help and support.

Call the National Alcohol and Other Drug Hotline on 1800 250 015 for free and confidential advice, information and counselling about alcohol and other drugs

Help and Support Services search

Find a service in your local area from our list. Simply add your location or postcode and filter by service type to quickly discover help near you.

If you're looking for other information or support options, send us an email at druginfo@adf.org.au


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Between 2001 and 2021 there were 833 fentanyl deaths reported in Australia. 774 (93%) deaths were attributable to pharmaceutical fentanyl and 37 (4%) to illicitly manufactured fentanyl (22 (3%) fentanyl analogues.8

Safe storage and disposal2

Fentanyl patches should be stored at room temperature, away from excess heat and moisture (not in the bathroom). To dispose of used fentanyl patches, fold the patch inwards on itself so that the adhesive sides meet, and return to the dispensing pharmacy. Wash your hands thoroughly with soap and water after disposing of the fentanyl patches. Do not put leftover or used fentanyl patches in the rubbish.2,10

  1. Upfal J. The Australian drug guide. 7th ed. Melbourne Black Inc.; 2006.
  2. NPS MedicineWise. Fentanyl Sandoz.: NPS MedicineWise; 2020
  3. Brands B, Sproule B, & Marshman J. Drugs & Drug Abuse. 3rd ed. Ontario: Addiction Research Foundation; 1998.
  4. Darke S, Lappin, J, & Farrell, M. The Clinician's Guide to Illicit Drugs. United Kingdom: Silverback Publishing 2019.
  5. Medline Plus. Fentanyl Transdermal Patch: U.S. Department of Health and Human Services; 2020
  6. Psychonaut Wiki. Fentanyl 2022 [cited: 17.01.2023].
  7. Hi-Ground. Opioids n.d. [cited: 05.01.2022].
  8. Roxburgh A Nielsen S. Twenty-year trends in pharmaceutical fentanyl and illicit fentanyl deaths, Australia 2001–2021. International Journal of Drug Policy. 2022;109.
  9. Roxburgh A Burns L Drummer O Pilgrim J Farrell M & Degenhardt L. Trends in fentanyl prescriptions and fentanyl‐related mortality in Australia. Drug and Alcohol Review. 2013;32(3):269-75.
  10. NPS MedicineWise. Accidental fentanyl exposure in children can be fatal: NPS MedicineWise; 2015

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