Synthetic opioids may have caused hundreds more UK deaths than thought

Research suggests deaths caused by a synthetic opioid that is hundreds of times stronger than heroin may have been underestimated by up to a third across the UK. Nitazenes are a class of synthetic opioids that are extremely potent, and up to 500 times stronger than heroin.

They were manufactured originally as a painkiller in the 1950s but their development was halted due to their extreme potencies resulting in a high risk of addiction. In 2024, the National Crime Agency reported that 333 fatalities across the UK were linked to the drug, but researchers at King’s College London say samples of the drug are likely being missed in postmortem toxicology tests.

The study tested samples from rats anaesthetised with the drug and found that on average only 14% of the nitazene present at the time of overdose was still detectable when handled under real-world pathology and toxicology conditions.

United Kingdom, London

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