
Fentanyl is a powerful painkiller. According to the Centers for Disease Control, it’s up to 100 times more potent than morphine.
Its strong potency means it can be used in operating rooms, to control pain after surgery and to alleviate pain for people with advanced cancer. But its effectiveness at relieving pain and increasing pleasure also have made it a popular street drug with dangerous risks of addiction, overdose and death.
What does fentanyl do? Read on to learn about the methods, benefits, risks and implications of using or misusing fentanyl.
Fentanyl is available in a variety of forms
Pharmaceutical fentanyl (Actiq, Fentora, Sublimaze) is a synthetic opioid — a lab-created compound — used under medical supervision. It can come in a variety of formats including:
- Nasal spray to treat cancer pain.
- Patch for the skin to address pain after surgery.
- Injection to relieve pain during and after surgery.
- Oral spray, tablet or lozenge to treat cancer pain.
Comparable to fentanyl, fentanyl analogs have similar chemical structure and effects. Common pharmaceutical industry fentanyl analogs used during surgery include sufentanil (Sufenta), alfentanil (Alfenta) and remifentanil (Ultiva). There are more than 30 nonpharmaceutical-grade fentanyl analogs circulating on the illicit drug market, many of which cannot be detected on standard urine drug screens.
What does fentanyl do to your body
As an opioid, fentanyl travels through your blood to attach to opioid receptors in brain cells. Once attached, fentanyl helps decrease feelings of pain. It remains one of the most commonly used opioids in controlled medical settings or advanced cancer pain. Fentanyl also can increase feelings of pleasure, often referred to as euphoria. Other effects can include drowsiness, nausea, confusion, constipation and addiction.
In addition to the euphoric feelings fentanyl can produce, those who are addicted to fentanyl can experience unpleasant withdrawal symptoms such as muscle pain, bone pain, diarrhea, vomiting, cold flashes and uncontrollable leg movements.
Whether prescribed or obtained illegally, there are serious risks to using fentanyl when it’s not dosed or used correctly — especially if you take too much or combine it with certain other medicines or alcohol. Fentanyl misuse can lead to unconsciousness, compromise respiratory function and lead to overdose resulting in death.
If you suspect that someone has overdosed on fentanyl, you might notice they have:
- A weak pulse.
- Very small pupils.
- Very slow or irregular breathing.
- Blue or gray edges around the mouth.
How fentanyl is misused
While fentanyl is legally manufactured and distributed in the U.S., it can be stolen, obtained with fraudulent prescriptions or made in illegal labs.
Illicitly manufactured fentanyl is illegal and can be sold as powder, nasal spray or pills that look like other prescription opioids. Fentanyl can be known by street names such as Apache, China Girl, Dance Fever or Goodfellas.
Illegal fentanyl can be used in the same ways as prescribed fentanyl. But it also can be misused by snorting or smoking. Some people who misuse fentanyl remove the gel contents of a fentanyl patch and then inject or ingest the contents. Others might freeze patches and then place frozen pieces under the tongue.
Additionally, some people use the ultrapotent fentanyl analog carfentanil, which is legally used to sedate large animals.
Fentanyl misuse is not only dangerous, but deadly
Because fentanyl is so potent, a very small dose — the Drug Enforcement Administration (DEA) says just two milligrams — can be lethal. High-potency opioids such as fentanyl, oxycodone (Oxycontin, Roxicodone) and methadone (Methadose, Methadone HCl Intensol) typically have more-serious risks.
Synthetic opioids like fentanyl are the most common drugs involved in overdose deaths. Between 2020 to 2021, 80,000 Americans died of problems related to synthetic opioids. And the death toll continues to rise dramatically:
- The number of synthetic opioid overdose deaths increased 97-fold between 1999 and 2021.
- Overdose deaths involving synthetic opioids in 2020 were 18 times the number of deaths in 2013.
The significant risks associated with taking street opioids stem from:
- No government regulation of ingredients, potency or dose.
- Unsanitary conditions in the illegal labs that create synthetic opioids.
- The dangerous methods people use to take the drugs — such as snorting, inhaling or injecting — which boost the potential for infection, serious health problems and overdose.
Fentanyl-laced illegal drugs
Producers of illicit fentanyl add it to or substitute it for other street drugs to increase profits and the potential for addiction — which keeps their customers coming back for more.
People who use drugs might not be aware they are taking fentanyl, yet the reality is that fentanyl-laced drugs are prevalent. In 2022, the DEA seized more than 50 million street pills laced with fentanyl — more than twice as many in 2021. Of the fentanyl-laced street pills analyzed by the DEA in 2022, 60% contained a potentially lethal dose of fentanyl. Fentanyl is increasingly found in street drugs that have been stamped with illegally purchased pill presses to look like other common pharmaceutical-grade drugs, such as oxycodone.
Efforts to prevent fentanyl overdoses
To help reduce the risk of fentanyl abuse, addiction and overdose, the Food and Drug Administration requires fentanyl prescriptions to be closely monitored to ensure the benefits outweigh the risks.
Fentanyl is covered under the Opioid Analgesic Risk Evaluation and Mitigation Strategy (REMS) to educate health care providers on treating and monitoring patients with pain.
Additionally, transmucosal immediate-release fentanyl (TIRF) REMS is a restricted distribution program to help ensure people use TIRF safely. TIRF medicines are for people with cancer who have been prescribed other, continuous opioids for their pain and need additional measures for breakthrough pain. To help ensure TIRF is distributed only to people who are opioid tolerant, TIRF REMS includes requirements such as:
- Prescribers must document a person’s opioid tolerance.
- Pharmacies must document and verify a person’s opioid tolerance before releasing TIRF.
- A patient registry to monitor for misuse, abuse, addiction and overdose.
Despite these programs, the internet has made buying almost anything online an option. It’s crucial to use extreme caution when getting medication or products marketed as “natural alternatives” from someone other than your health care provider. There have been situations where people thought they were buying natural products, including weight-loss supplements, cannabis and anti-anxiety medications, and instead got fentanyl-laced drugs.
Resources for those using or abusing opioids
Naloxone — also known by the brand names such as Narcan and Kloxxado — is a prescription medication that reverses an opioid overdose. While it works quickly, naloxone is a temporary solution that works for 30 to 90 minutes. It’s available both for those who have been prescribed fentanyl and those who are misusing fentanyl. Naloxone may be available without a prescription at community-based programs, local public health groups or local health departments. In many states, the medicine may be requested from a pharmacy without a patient-specific prescription.
With the popularity of drug dealers mixing fentanyl into other drugs, fentanyl test strips can help people who use drugs identify whether what they are taking contains fentanyl or not. These small, paper strips can be obtained at needle-exchange sites, are easy to use and only take minutes to interpret.
When used safely under the supervision of a health care team, fentanyl can be a tremendous tool to help alleviate pain. When used in ways not prescribed or obtained from illicit sources, fentanyl can be deadly. To learn more about the unique risks and benefits of opioids, read “Ending the Crisis: Mayo Clinic’s Guide to Opioid Addiction and Safe Opioid Use.”

Relevant reading
Ending the Crisis
An authoritative guide to understanding the current opioid crisis in America and how it can be solved.
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