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Nitazene links

Some things you should know about nitazenes

You might have been hearing a lot about nitazenes lately. Recently, stories about nitazenes burst into the media, with a spate of stories appearing online and on multiple Denver TV stations in late December and early January.

Nitazenes are among the latest drugs that contribute to fatal opioid overdoses. The Colorado Department of Public Health and Environment has recorded 13 drug overdose deaths with mention of nitazene or nitazene analogs from August 2021 to October 2023.

All the deaths involved multiple substances, and all were associated with fatal drug overdose as the underlying cause. Ages range from late teens to late 60s, and all occurred in the Front Range, defined as Larimer County to El Paso County, according to the CDPHE.

Here are some facts about nitazenes, based on a literature search of academic journals and government websites.

Naloxone works on nitazenes

Maybe the most important point first – naloxone has been proven to reverse nitazene overdoses, according to multiple studies and sources.

However, an investigation of records from hospital emergency departments that was published by the JAMA Network found it often takes more doses of naloxone to reverse a overdose when nitazene is involved than it would take to reverse a fentanyl overdose. They call for further study.

While researchers continue their work, the message for the public remains the same: use naloxone for any suspected opioid overdose and call 911 immediately.

What are nitazenes?

Nitazenes are a category of synthetic opioids developed in the 1950s to be pain relievers but never received approval for medical use. Examples of nitazenes include isotonitazene, protonitazene, etonitazene, and metonitazene. Around 2019, different nitazenes began appearing in the drug supply across the country, according to the DEA.

Multiple studies have found nitazenes are added to drugs like fentanyl, heroin, methamphetamine, illicit benzodiazepines, counterfeit pills, or other substances.

A CDC case study found that nitazene-contaminated drugs are most frequently injected, although smoking, snorting, and ingestion also were reported.

Nitazenes are unrelated to xylazine, which is not an opioid, but is sometimes combined with fentanyl. Like nitazenes, xylazine remains uncommon in Colorado, according to the CDPHE.

What do nitazene overdoses look like, and how should people respond?

Nitazenes are opioids, so overdoses look like other opioid overdoses. Signs include the following:

  • breathing that has slowed, is halting, or has stopped
  • non-responsiveness
  • loss of consciousness
  • pinpoint pupils
  • blue or grey skin, lips, and/or fingernails

Are nitazenes like fentanyl?

Like fentanyl, nitazenes are synthetic opioids, which means that naloxone reverses an overdose that involves nitazene. Like fentanyl and its analogs, nitazenes are manufactured in illegal laboratories.
However, the chemical structures of the nitazenes and fentanyl analogs are different. Scientists are studying if and how that matters when it comes to treating nitazene overdoses, but they do know that naloxone will reverse an overdose.

Are they more dangerous than fentanyl?

Some nitazenes are more potent than fentanyl, according to the CDC. However, their potency can vary. Research has shown that naloxone is effective in reversing overdoses that includes a nitazene but reports from hospital emergency departments and health departments show that it takes more doses of naloxone to reverse nitazene overdoses.

How do people become exposed to nitazene?

Nitazenes appear to be contaminating other drugs, similar to how fentanyl has. Users will not know if a nitazene analog is present, as they are tasteless, odorless, and not visible. According to a study of overdose survivors that appeared in JAMA Network Open, “many patients may believe they are using heroin.”  

What can we do about this?

Both the CDC and CDPHE have stated their belief that the best way forward is to let people know about the presence of nitazenes in the drug supply and keep educating the public about the efficacy of naloxone, the need to administer naloxone and call 911 immediately, and the importance of other harm-reduction tactics such as never using alone.

They also say that public health experts will continue to watch for the emergence of new drugs like novel synthetic opioids and educating medical providers and first responders about the potential need to administer more naloxone.

Why are nitazenes in the news now?

What prompted the nitazene coverage in Colorado was the Boulder County Coroner’s office discovering two men had died of drug overdoses with nitazenes in their systems. Of particular note was that toxicology reports found that one of the nitazenes, etonitazene, appears to have been modified by chemists to have what the coroner’s news release calls “its newly identified [chemical] structure.”

Whether that modification mattered is to be determined, but it shows that new drugs continue to appear in the drug supply. Interested in learning more about novel psychoactive substances in the United States? Check out the Novel Psychoactive Substances Discovery website from the Center for Forensic Science Research & Education (CFSRE):