More deaths can likely be attributed to opioids than previously thought, and that is largely thanks to a substance called nitazene. The synthetic drug can be five to nine times stronger than fentanyl, which is already approximately 25 to 50 times stronger than heroin. Nitazene is often hidden in other products and difficult to test for, so it often goes undetected.
How prevalent is nitazene?
Nitazene was first developed in the 1950s as an analgesic, but was never approved for medical use. Instead, it was “limited to those researching opioid pharmacology,” said Rolling Stone. Nitazene’s presence mostly remained that way until 2019, when the drug emerged on the street market in Europe and the U.S. From there, its presence accelerated. In 2023, 20 different nitazenes were reported by 28 countries to the UN, according to the World Drug Report 2025. Then in 2024, “more new nitazenes than new fentanyl analogs were being reported,” accounting for “almost 50% of all reported opioid NPS (novel psychoactive substances).”
In the U.S., 320 overdose deaths in 2023 reportedly involved nitazenes, according to the World Drug Report. However, this number is likely understated. The country still mostly “relies on toxicology panels built for yesterday’s drug supply,” said Time. The antiquated panels can “reliably identify heroin, oxycodone and fentanyl,” but they “fail to catch nitazenes, brorphine or other new synthetic analogs.” Without proper identification, “policymakers and public health professionals chase outdated trends.” A “person who dies with both cocaine and a nitazene in their system might still be coded as a ‘cocaine death.’”
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Fentanyl is still considered the number one cause of opioid deaths, accounting for 48,422 deaths in the U.S. in 2024. But there have been “reported signs of a declining fentanyl market” within the country, with “declining purity and a smaller number of seizures of fentanyl pills.” The rise in nitazenes “may be a response to efforts to reduce the supply of other opioids,” said Ryan Marino, a toxicologist and expert in addiction medicine at University Hospitals in Cleveland, to Rolling Stone. “In almost every case where nitazenes are found, they are added to other drugs, primarily fentanyl, and not advertised as containing nitazenes when sold.”
How dangerous is it?
Even very small doses of nitazene can be deadly. The lethality of fentanyl is “anywhere between 10 and 20 grains of salt,” said Frank Tarentino, the special agent in charge of the Drug Enforcement Administration’s New York lab, to CBS News. With nitazene, “we're talking about anywhere from one grain or less.” Much of the exposure to nitazene comes inadvertently. It has been found in “vapes sold as containing cannabis, in pills shaped as teddy bears supposed to be MDMA, in powder trafficked as cocaine, in counterfeit pain medication,” said The Guardian.
Synthetic opioids are so dangerous that first responders have to avoid inhalation when addressing an overdose situation. The drugs “slow down the part of your brain that tells you to breathe,” said Dimitri Gerostamoulos, an associate professor and the chief toxicologist at the Victorian Institute of Forensic Medicine, to The Guardian. “This is what causes respiratory depression. We sometimes refer to this as the ‘sleepy death.'” It can also cause paralysis and seizures. Luckily, nitazene is an “opioid, and naloxone blocks opioids,” said Chinazo Cunningham, the commissioner of the New York State Office of Addiction, Services and Supports, to CBS News. “If it's a very powerful opioid, it may take a couple of doses.”
