Researchers from King’s College London suggest that deaths caused by nitazenes, an extremely powerful class of synthetic opioid, may be substantially undercounted across the UK. A situation of concealing the true scale of an escalating public health threat. Nitazenes can be up to 500 times stronger than heroin and pose an exceptionally high risk of overdose.
Although scientists originally developed them in the 1950s as potential painkillers, their extreme potency led to the abandonment of their medical use. Today, these substances have re-emerged in illegal drug markets with deadly consequences.
Official figures from the National Crime Agency recorded 333 nitazene-linked deaths in the UK in 2024. However, the King’s College research indicates that the actual number may be up to a third higher. The researchers argue that standard postmortem toxicology tests often fail to detect nitazenes, leading to systematic underreporting. Their study showed that nitazenes degrade rapidly after death, meaning only a small fraction of the drug remains detectable by the time samples reach laboratories.
To demonstrate this, the research team conducted experiments using anaesthetised rats exposed to nitazenes. Under conditions that replicate real-world pathology and toxicology handling, tests detected only about 14% of the drug present at the time of overdose. The researchers then applied statistical modelling to data from the UK National Programme on Substance Use Mortality. Their analysis revealed a significant excess of unexplained drug deaths in Birmingham in 2023, consistent with widespread non-detection of nitazenes.
Public Pressure
Dr Caroline Copeland, the study’s lead author, warned that inaccurate mortality data undermines efforts to design effective harm reduction strategies. When authorities underestimate deaths, policymakers allocate insufficient resources and implement interventions that fail to match the scale of the crisis. Copeland stressed that behind the missing statistics are real people who die suddenly, families left without clear answers, and communities absorbing a growing but largely invisible toll.
The government acknowledged the severity of drug-related deaths and stated that it remains alert to emerging threats. Officials highlighted ongoing collaboration with health and law enforcement agencies, as well as new measures such as trained dogs capable of detecting fentanyl and nitazenes. Despite these efforts, the research underscores a troubling reality.
Without accurate detection and data, the UK risks fighting a lethal opioid crisis with incomplete information, allowing preventable deaths to continue.
Reference
Thomas, T. (2026, February 9). Synthetic opioids may have caused hundreds more UK deaths than thought. The Guardian. https://www.theguardian.com/society/2026/feb/09/synthetic-opioids-nitazenes-more-uk-deaths-than-thought?CMP=Share_AndroidApp_Other