Nitazenes Emerge as Deadly New Threat in US Drug Supply, 40 Times Stronger Than Fentanyl

Ashley Delgado had dreams of becoming a doctor. Growing up in Cleveland, Ohio, she excelled in science and Latin, maintaining a high GPA through high school while harboring ambitions of healing others. But a leg injury in her mid-20s led to an OxyContin prescription that would alter the trajectory of her life.

What followed was a yearslong descent through addiction — from prescription opioids to methamphetamine, then heroin, and finally fentanyl. With her family's support, Ashley entered rehabilitation and moved into a sober living home. On an early summer morning in 2023, however, her body was found on a dead-end street outside the city. She was 29 years old.

Toxicology tests revealed something her family had never heard of: protonitazene and metonitazene, powerful synthetic opioids from a class of drugs known as nitazenes. These compounds, developed in the 1950s as potential painkillers but abandoned because they were deemed unsafe for medical use, can be up to 40 times more potent than fentanyl and 500 times stronger than heroin.

The Scale of an Emerging Crisis

According to data from the Centers for Disease Control and Prevention's State Unintentional Drug Overdose Reporting System (SUDORS), more than 1,100 fatalities involving nitazenes have been confirmed since 2019. But experts believe the actual death toll could be as high as 2,000, with many cases going undetected because forensic laboratories weren't routinely testing for these compounds until recently.

"There are only limited forensic toxicology labs that test for nitazenes," explained Alex Krotulski, director of the Centre for Forensic Science Research and Education in Pennsylvania. "If a nitazene was present and the lab didn't test for it, the number wouldn't appear in SUDORS."

The most recent years with available data — 2023 and 2024 — were the deadliest on record for nitazene-involved overdoses, with 747 confirmed deaths in that two-year period alone. The United States has reported 26 different kinds of nitazenes since 2019, the second-highest number globally after Canada, according to figures provided to investigators by the United Nations Office on Drugs and Crime.

How Nitazenes Enter the Supply Chain

Unlike traditional opioid trafficking routes, nitazenes predominantly enter the United States through online channels — both on the clear web and dark web markets. The Drug Enforcement Administration began tracking nitazene-related seizures around 2014, but it wasn't until 2019 that authorities observed a marked increase in their presence.

What makes nitazenes particularly dangerous is how they're distributed. The compounds are frequently laced into other substances to increase potency, putting unsuspecting users at risk. Someone seeking oxycodone, fentanyl, or even stimulants like cocaine may unknowingly consume a substance containing nitazenes, with potentially fatal consequences given their extraordinary potency.

A Bellingcat investigation conducted last year found more than 1,000 advertisements for nitazenes populating online marketplaces, forums, and dark web platforms. The current investigation, conducted in partnership with STAT News and Signal Cleveland, represents the most comprehensive examination yet of how these substances infiltrate American communities.

Federal Response and Regulatory Challenges

Federal authorities have taken aggressive action against nitazenes, scheduling dozens of specific compounds as illegal substances through the DEA's controlled substances framework. Undercover operations have targeted distribution networks, and indictments have been filed against China-based chemical manufacturing companies and their employees.

The White House has also imposed tariffs on China, where many laboratories manufacturing and supplying nitazenes and fentanyl precursors are believed to operate. Yet despite these enforcement efforts, the compounds continue spreading across the country, illustrating the adaptive nature of synthetic drug markets that innovate faster than regulatory responses can contain them.

This pattern — enforcement pressure driving innovation toward more dangerous and less detectable substances — has become a defining characteristic of the evolving overdose crisis. As authorities crack down on fentanyl and its analogues, manufacturers pivot to unscheduled alternatives that often prove more lethal.

The Clinical Challenge

For healthcare providers and first responders, nitazenes present unique clinical challenges. Standard toxicology screens frequently miss these compounds, leading to underreporting and delayed recognition of their involvement in overdose cases. When nitazenes are detected, their extreme potency often requires multiple doses of naloxone — the opioid overdose reversal medication — to achieve reversal.

The emergence of nitazenes comes at a particularly precarious moment in the overdose crisis. After years of relentless increases, national overdose deaths have begun declining — falling 14% in 2024 to approximately 80,000 fatalities. But this fragile progress now faces threats from multiple directions: nitazenes, the veterinary tranquilizer xylazine ("tranq dope"), medetomidine ("rhino tranq"), and other novel synthetic opioids like cychlorphine and orphines.

Ohio Bears the Brunt

Ohio has emerged as an epicenter of nitazene activity. Ashley Delgado's death in Cleveland reflects a broader pattern affecting communities across the state. The compounds have been detected in toxicology reports from multiple counties, with metropolitan areas experiencing particularly high concentrations of cases.

The state's experience illustrates how nitazenes complicate already challenging public health responses. Communities that have invested heavily in naloxone distribution, medication-assisted treatment expansion, and harm reduction infrastructure now face a threat that may require adapted protocols and enhanced surveillance.

Implications for Harm Reduction

The nitazene crisis forces difficult questions about harm reduction strategies that have helped drive down overdose deaths in recent years. Fentanyl test strips, which detect the presence of fentanyl in drug samples, cannot identify nitazenes. Naloxone, while still effective, may require higher or repeated doses to reverse nitazene-involved overdoses.

Public health officials are grappling with how to adapt messaging and interventions for a drug supply that grows more unpredictable by the year. The "chemical cat and mouse" dynamic — where enforcement pressure drives innovation toward novel, often more dangerous substances — suggests that technical solutions alone may be insufficient without addressing underlying demand and the structural factors driving substance use.

Looking Forward

For James Taylor, Ashley's father, the statistics represent something deeply personal. "I have lost my father, my grandmother — that hurts," he said. "But when you lose your child, that's the worst thing on the planet, because they're not supposed to go before you."

His daughter's story — a promising student, a medical injury, a prescription, and a yearslong struggle with addiction that ended with an overdose from substances most Americans have never heard of — encapsulates the evolving nature of the overdose crisis. The drugs change, the potency increases, but the human toll remains devastatingly consistent.

As nitazenes continue spreading across the United States, public health officials, policymakers, and communities face the challenge of responding to a threat that defies easy categorization. These are not traditional opioids, not conventional street drugs, but something new — synthetic compounds of extraordinary potency that can be ordered online and delivered through the mail, circumventing traditional drug trafficking infrastructure entirely.

The 1,100 confirmed deaths represent only what we know. The true toll, like the full scope of nitazene distribution, remains hidden in toxicology reports that were never run, cases that were never identified, and families who may never learn what truly caused their loved one's final overdose.