Nitazenes are a group of synthetic opioids that have started showing up in the illicit drug supply in the United States and other countries. They are not household names like heroin, fentanyl, oxycodone, or morphine, but they can be just as dangerous, and in some cases, even more dangerous.
The concern is simple. Nitazenes are powerful opioids that can slow breathing, cause loss of consciousness, and lead to fatal overdose. Some nitazene analogs have tested as more potent than fentanyl, while others may be closer to fentanyl in strength. That matters because a person may think they are taking heroin, fentanyl, oxycodone, Xanax, cocaine, or another street drug without knowing that a nitazene has been added. The CDC has reported that nitazene deaths may be undercounted because traditional toxicology panels do not always detect them.
For people using opioids, counterfeit pills, or powders from the street supply, nitazenes are one more reason that drug use has become unpredictable. A person cannot reliably know what is in a pill or powder by looking at it. They also cannot safely judge potency by past experience, because the same-looking product may contain a very different drug from one batch to the next.
What Are Nitazenes?
Nitazenes, also called benzimidazole-opioids, are synthetic opioids that belong to a class of compounds originally developed in the late 1950s. They were researched as possible pain-relieving drugs, but they were never approved for medical use in the United States. The DEA describes benzimidazole-opioids, or nitazenes, as structurally related substances used for opioid-like effects. The agency also notes that their increased identification in seized drug material and toxicology cases since 2019 has caused serious public health concern.
Like other opioids, nitazenes act on mu-opioid receptors in the brain. These are the same receptor systems involved with heroin, fentanyl, morphine, and prescription opioid pain medications. When opioids activate these receptors, they can reduce pain and produce euphoria. They can also slow breathing. When breathing slows too much, oxygen levels drop, the person may become unconscious, and overdose can become fatal.
The word “nitazenes” does not refer to only one drug. It refers to a class of related synthetic opioids. Examples include isotonitazene, metonitazene, protonitazene, etonitazene, butonitazene, flunitazene, etodesnitazene, and others. Each analog can have different potency, duration, and risk. This makes nitazenes hard to understand for the general public and difficult to track in real time.
Why Are Nitazenes So Dangerous?
Nitazenes are dangerous because they combine several high-risk factors at once. They can be extremely potent. They may be mixed into other drugs without the person knowing. They may not show up on routine drug screens. They can cause fast respiratory depression. And because many people have never heard of them, they may not know what risk they are taking.
The CDC reported 52 nitazene-involved fatal overdoses in Tennessee from 2019 through 2021, with no cases found in 2019, 10 in 2020, and 42 in 2021. All of those nitazene-involved overdoses also involved multiple substances. Fentanyl, methamphetamine, amphetamine, and flualprazolam were among the co-occurring substances reported.
That pattern is important. Many nitazene deaths may not involve a person intentionally seeking nitazenes. Instead, they may involve a person using what they believe is another drug. This is similar to the way fentanyl entered counterfeit pills and stimulant supplies. When a drug is hidden inside another substance, overdose risk rises because the person is not able to prepare for the true strength of what they are taking.
Nitazenes vs. Fentanyl vs. Heroin
The biggest mistake people can make is assuming that all opioids carry the same level of risk. They do not. Heroin, fentanyl, and nitazenes all act as opioids, but their potency and unpredictability can differ.
| Substance | What It Is | Key Risk | Why It Matters |
|---|---|---|---|
| Heroin | An illicit opioid derived from morphine | Overdose, addiction, infection risk, withdrawal | Heroin strength varies and may now be mixed with fentanyl or nitazenes. |
| Fentanyl | A powerful synthetic opioid used medically and illicitly | Very small amounts can cause overdose | Fentanyl is often found in counterfeit pills and powders. |
| Nitazenes | A class of synthetic benzimidazole opioids | Some analogs may be stronger than fentanyl | They may be missed by standard toxicology tests and hidden in other drugs. |
| Counterfeit oxycodone pills | Fake pills made to look like prescription opioids | May contain fentanyl, nitazenes, or other synthetic opioids | A pill can look legitimate but contain no real oxycodone. |
| Polysubstance mixtures | More than one drug used together or mixed in the supply | Combined sedation, cardiac strain, respiratory depression | Nitazene-involved deaths often involve multiple substances. |
Some nitazenes are reported to greatly exceed fentanyl in potency, while metonitazene may be closer to fentanyl. That means one nitazene cannot be treated as identical to another. The danger is not just that nitazenes are “strong.” The danger is that the person using the drug often has no idea which analog is present, how much is present, or what else is mixed with it.
Where Are Nitazenes Showing Up?
Nitazenes may appear in counterfeit pills, powders, and other illicit drug products. They can be found alongside fentanyl or other opioids, and they may also be present in drugs sold as something else. This is one reason opioid overdose prevention has become more complicated. A person may believe they are using one substance while actually being exposed to several.
The DEA has reported that benzimidazole-opioids have been identified in U.S. toxicology cases and drug seizures. DEA’s fact sheet also notes that toxicology analyses have co-identified benzimidazole-opioids with other opioids, primarily fentanyl, as well as stimulants and benzodiazepines.
This matters for treatment and prevention. Someone who uses opioids may also be using benzodiazepines, alcohol, cocaine, methamphetamine, or other substances. When opioids are combined with sedatives, breathing can slow even more. When opioids are combined with stimulants, a person may misread how impaired they are, then crash into heavy sedation later.
Signs of a Nitazene or Opioid Overdose
A nitazene overdose can look like other opioid overdoses. The most important sign is slowed, weak, or stopped breathing. A person may not respond when spoken to or shaken. Their lips, skin, or fingernails may look blue, gray, pale, or ashy depending on skin tone. Their body may become limp. They may make choking, gurgling, or snoring sounds. Their pupils may become very small.
Any suspected opioid overdose should be treated as a medical emergency. Call 911, give naloxone if available, begin rescue breathing or CPR if trained to do so, and stay with the person until emergency help arrives. Naloxone can reverse opioid overdose, but the CDC notes that multiple doses may be needed with potent synthetic opioids such as nitazenes.
Do not assume someone is “sleeping it off.” Opioid overdose can become fatal because the person is not getting enough oxygen. Minutes matter.
Can Naloxone Reverse a Nitazene Overdose?
Naloxone, also known by the brand name Narcan, can help reverse an opioid overdose by blocking opioids at the receptor level. CDC reporting states that naloxone has been effective in reversing nitazene-involved overdoses, although multiple doses may be needed because of potency.
That does not mean naloxone is a perfect safety net. Naloxone may wear off before the opioid does. A person can start breathing again and then become sedated again later. That is why emergency medical care is still needed after naloxone is given.
People who use opioids, know someone using opioids, or live in a home where opioids may be present should consider keeping naloxone available. It is also important for family members and friends to know how to use it before an emergency happens.
Why Drug Testing May Miss Nitazenes
One of the most troubling parts of the nitazene problem is detection. Standard toxicology panels may not always include nitazenes. The CDC specifically noted that traditional laboratory panels do not always capture nitazenes, which means deaths may be undercounted.
This also matters for people who rely on basic drug tests to tell them what they took. A negative result for one opioid does not mean a substance is safe. A test may not be designed to detect newer synthetic opioids. Drug checking technology is improving, but illicit drug markets change quickly.
For families, this can be confusing. A loved one may overdose from a substance they did not know they were taking. A toxicology report may identify fentanyl, benzodiazepines, stimulants, or other substances, while a newer opioid may be missed unless specialized testing is done.
Nitazenes and Opioid Addiction
Not every person exposed to nitazenes is intentionally looking for them. However, nitazenes are still part of the larger opioid addiction crisis. People with opioid use disorder may seek heroin, fentanyl, oxycodone, or other opioids and unknowingly encounter nitazenes in the supply. Others may use counterfeit pills recreationally and underestimate the risk.
Opioid addiction changes the brain and body over time. Tolerance can build, meaning a person needs more of the drug to feel the same effect or to avoid withdrawal. But tolerance does not protect someone from unpredictable potency. A person may tolerate one batch and overdose on another.
Withdrawal can also keep people trapped. Opioid withdrawal may cause muscle aches, nausea, vomiting, diarrhea, anxiety, insomnia, sweating, chills, and intense cravings. Fear of withdrawal often pushes people back to use, even when they want to stop.
That is why treatment needs to address more than the drug itself. Effective opioid addiction treatment may include medical detox, residential treatment, therapy, relapse prevention planning, psychiatric support, family education, and aftercare.
When to Seek Treatment
A person should consider treatment if they are using opioids and cannot stop, needing more to feel the same effect, using alone, buying pills or powders from nonmedical sources, experiencing withdrawal, overdosing, mixing opioids with alcohol or benzodiazepines, or continuing to use despite serious consequences.
Treatment is especially important when synthetic opioids are involved. The risk is no longer limited to the substance a person thinks they are using. Fentanyl, nitazenes, xylazine, benzodiazepines, and other substances can all appear in the illicit supply. This makes each episode of use more unpredictable.
Medical detox can help stabilize the body during withdrawal. Residential treatment can help a person step away from the environment and routines connected to use. Therapy can help address trauma, depression, anxiety, grief, relationship problems, and other factors that often keep addiction active. Aftercare can help maintain progress once someone leaves structured treatment.
Getting Help for Opioid Addiction in Los Angeles
Sanctuary Treatment Center provides addiction treatment in Los Angeles for people struggling with opioids and other substances. If you or someone you love is using heroin, fentanyl, counterfeit pills, or other street opioids, waiting can be dangerous. The drug supply is too unpredictable to rely on willpower, tolerance, or past experience.
Recovery starts with one honest conversation. A treatment team can help you understand what level of care may be appropriate, what detox may involve, and how to begin safely.
Call Sanctuary Treatment Center today to speak with someone about opioid addiction treatment in Los Angeles. Help is available, and you do not have to figure this out alone.
Frequently Asked Questions About Nitazenes
What are nitazenes?
Nitazenes are synthetic opioids also known as benzimidazole-opioids. They were first developed decades ago as possible pain medications, but they were never approved for medical use in the United States. Today, they are a concern because they have appeared in illicit drug supplies and have been linked to fatal overdoses.
Are nitazenes stronger than fentanyl?
Some nitazene analogs may be stronger than fentanyl, while others may be closer to fentanyl in potency. The danger is that a person usually does not know which nitazene analog is present or how much is in the drug they are taking.
Can nitazenes cause withdrawal symptoms?
Yes. Nitazenes are opioids, so repeated use can lead to physical dependence and opioid withdrawal. Withdrawal symptoms may include sweating, chills, muscle aches, nausea, diarrhea, anxiety, insomnia, and strong cravings.
What withdrawal symptoms happen with synthetic opioids like nitazenes?
Synthetic opioid withdrawal can cause body aches, stomach cramps, nausea, vomiting, diarrhea, sweating, restlessness, anxiety, trouble sleeping, and cravings. Symptoms can feel intense, but medical detox can help reduce risks and provide support.
How long does nitazene withdrawal last?
Opioid withdrawal timelines vary depending on the drug used, the amount used, the person’s health, and whether other substances are involved. Short-acting opioids may cause symptoms within hours, while longer-acting opioids may have a slower timeline. A medical team can help evaluate what to expect.
Can naloxone reverse nitazene overdose?
Naloxone can reverse opioid overdose, including overdoses involving nitazenes, but multiple doses may be needed. Always call 911 after giving naloxone because overdose symptoms can return after naloxone wears off.
Do fentanyl test strips detect nitazenes?
Fentanyl test strips are designed to detect fentanyl, not all nitazenes. Some drug-checking tools may miss newer synthetic opioids. A negative test does not mean a drug is safe.
Can nitazenes be found in fake pills?
Yes. Nitazenes may appear in counterfeit pills or other illicit drug products. A pill that looks like oxycodone, Xanax, or another prescription medication can contain fentanyl, nitazenes, or other dangerous substances.
APA Sources
Centers for Disease Control and Prevention. (2022). Notes from the field: Nitazene-related deaths — Tennessee, 2019–2021. Morbidity and Mortality Weekly Report, 71(37), 1196–1197. https://www.cdc.gov/mmwr/volumes/71/wr/mm7137a5.htm
Drug Enforcement Administration, Diversion Control Division. (2026). Benzimidazole-opioids: Other name: Nitazenes. U.S. Department of Justice. https://www.deadiversion.usdoj.gov/drug_chem_info/benzimidazole-opioids.pdf
Drug Enforcement Administration. (n.d.). One pill can kill. U.S. Department of Justice. https://www.dea.gov/onepill