What is fentanyl?

hand holding a bottle of fentanyl and a syringe

The Bottom Line

Fentanyl is a powerful opioid that is a common contaminant of illicit drugs. Fentanyl acts on the brain to cause life-threatening respiratory depression. The antidote naloxone (Narcan®) can reverse the effects of fentanyl overdose.

woman's hand reaching for pills

The Full Story

What is fentanyl?

Fentanyl is a synthetic, opioid medication initially created in 1960 during a quest to develop safer and more potent alternatives to the narcotic analgesic medications that were available at the time. Fentanyl was introduced into the United States as a powerful intravenous anesthetic and was later developed into a skin patch as well as oral formulations for pain relief. 

 

What is fentanyl used for?

Currently, prescription fentanyl is used for pain management and is available in oral, nasal, injectable, and transdermal formulations. Fentanyl analogs or “chemical cousins”, including sufentanil and alfentanil, are used as human anesthetic drugs in the United States. Another powerful fentanyl analog, carfentanil, is a veterinary anesthetic for large animals including moose, rhinoceros, and elephants. 

 

What does fentanyl do?

Like other opioid drugs, fentanyl acts on the brain to cause sedation, analgesia, and euphoria. Like other opioids, fentanyl also causes respiratory depression, or a slowing of the respiratory or breathing rate. Fentanyl is highly fat soluble, which means that it can transfer from the blood into the brain quickly. This causes a rapid onset of clinical effects after the drug is used. Fentanyl is a very powerful opioid and is approximately 100 times more potent than morphine. Because it is so strong, very small amounts (as little as 2 milligrams) can cause severe and rapid respiratory depression and death in humans. Deaths from fentanyl overdose are due to the respiratory depressant properties of the drug. When breathing slows significantly or stops, oxygen is no longer delivered to the brain, heart, and other organs, causing organ failure and death. 

 

Is fentanyl addictive?

Due to its potent analgesic properties, fentanyl is also recognized as a drug of abuse. Initial reports of fentanyl abuse were related to prescription preparations, but in recent years there has been an increase in deaths related to illicit, nonpharmaceutical fentanyl formulations. Illicit fentanyl is made from chemicals in clandestine laboratories. It is often trafficked into the United States from other countries and sold as pills or powders. In many cases, these illicit formulations of fentanyl look like oxycodone or other prescription opioid tablets (pill presses or molds that create professional-looking tablets can be purchased online). Fentanyl is also added to heroin, cocaine, and methamphetamine and is a common contaminant of illicit drugs in the United States. People who purchase and use street drugs, as well as the people who sell the drugs, may be completely unaware that a particular powder or pill contains fentanyl instead of another drug. Also, there is no way to tell how much fentanyl may be present in a particular street drug unless the drug is tested by a reputable laboratory. Given fentanyl’s potency, widespread presence in the illicit drug supply in the United States, and ability to cause death after exposure to tiny amounts of the drug, it is easy for people to unknowingly overdose on fentanyl.

 

What is fentanyl overdose?

Fentanyl overdose can occur after the drug is injected intravenously, consumed, inhaled, or smoked. Signs and symptoms of fentanyl overdose, including slow or absent respirations, generally occur within minutes. Fentanyl can be detected in the body for several days after its last use, although most standard urine drug screening tests available in hospitals are not designed to detect the presence of fentanyl. Bystanders, first responders, and medical personnel who treat victims of fentanyl overdose are highly unlikely to experience adverse reactions or poisoning after accidental skin contact with fentanyl, as the drug is not easily absorbed through intact skin (the transdermal patch formulations of fentanyl are specially designed to promote transfer of drug through the skin).    

Fortunately, there is an antidote for fentanyl and other opioid overdoses, called naloxone or Narcan®. Naloxone helps reverse the respiratory depressant effect of fentanyl. It can be given as a nasal spray or injection and can help prevent fentanyl-related deaths when it is administered within a short period of time after an overdose. Naloxone is currently available without a prescription in every state and can be obtained from pharmacies. Naloxone acts quickly to reverse the effects of opioid overdose, but patients who receive naloxone still require medical evaluation and close observation for recurrence of overdose symptoms.

If you have questions about poisoning from opioids, including fentanyl, contact Poison Control for expert advice. There are two ways to contact Poison Control in the United States: online at www.poison.org, and by phone at 1-800-222-1222. Both options are free, confidential, and available 24 hours a day.


Kelly Johnson-Arbor, MD
Medical Toxicologist

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • Do not use street drugs or other illicit substances.
  • Do not take medications that are not prescribed for you.
  • If you or a loved one have been prescribed an opioid pain medication, ask your doctor for a prescription for naloxone (Narcan®) or visit naloxoneforall.org to obtain naloxone. This medication can help reverse the effects of an opioid overdose.

This Really Happened

Case 1: A 17-year-old boy was found unresponsive, with pinpoint pupils and a slow respiratory rate. He was treated with naloxone, and his mental status and respiratory rate improved. He was admitted to an intensive care unit for observation. His brother reported that the patient had taken a blue tablet labeled “M30”, which the patient believed to be oxycodone. An expanded urine toxicology assay was positive for metabolites of both fentanyl and cocaine.

Case 2: A 11-month-old girl ingested a blue tablet she found while crawling around a new apartment. She developed somnolence and a slow respiratory rate, and was treated with naloxone. An expanded urine toxicology assay was positive for fentanyl, methamphetamine, acetaminophen, and tramadol.


For More Information

Counterfeit Pills (Department of Justice/Drug Enforcement Administration)

Fentanyl (Department of Justice/Drug Enforcement Administration)

Fentanyl DrugFacts (National Institutes of Health)

Lifesaving Naloxone (Centers for Disease Control and Prevention)


References

Armenian P, Vo KT, Barr-Walker J, Lynch KL. Fentanyl, fentanyl analogs and novel synthetic opioids: A comprehensive review. Neuropharmacology. 2018 May 15;134(Pt A):121-132.

Joynt PY, Wang GS. Fentanyl contaminated "M30" pill overdoses in pediatric patients. Am J Emerg Med. 2021 Dec;50:811.e3-811.e4. 

Lötsch J, Walter C, Parnham MJ, Oertel BG, Geisslinger G. Pharmacokinetics of non-intravenous formulations of fentanyl. Clin Pharmacokinet. 2013 Jan;52(1):23-36. 

Moss MJ, Warrick BJ, Nelson LS, McKay CA, Dubé PA, Gosselin S, Palmer RB, Stolbach AI. ACMT and AACT Position Statement: Preventing Occupational Fentanyl and Fentanyl Analog Exposure to Emergency Responders. J Med Toxicol. 2017 Dec;13(4):347-351.

Pergolizzi JV Jr, Dahan A, Ann LeQuang J, Raffa RB. Overdoses due to fentanyl and its analogues (F/FAs) push naloxone to the limit. J Clin Pharm Ther. 2021 Dec;46(6):1501-1504.

Zawilska JB, Kuczyńska K, Kosmal W, Markiewicz K, Adamowicz P. Carfentanil - from an animal anesthetic to a deadly illicit drug. Forensic Sci Int. 2021 Mar;320:110715.

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • Do not use street drugs or other illicit substances.
  • Do not take medications that are not prescribed for you.
  • If you or a loved one have been prescribed an opioid pain medication, ask your doctor for a prescription for naloxone (Narcan®) or visit naloxoneforall.org to obtain naloxone. This medication can help reverse the effects of an opioid overdose.

This Really Happened

Case 1: A 17-year-old boy was found unresponsive, with pinpoint pupils and a slow respiratory rate. He was treated with naloxone, and his mental status and respiratory rate improved. He was admitted to an intensive care unit for observation. His brother reported that the patient had taken a blue tablet labeled “M30”, which the patient believed to be oxycodone. An expanded urine toxicology assay was positive for metabolites of both fentanyl and cocaine.

Case 2: A 11-month-old girl ingested a blue tablet she found while crawling around a new apartment. She developed somnolence and a slow respiratory rate, and was treated with naloxone. An expanded urine toxicology assay was positive for fentanyl, methamphetamine, acetaminophen, and tramadol.