When comparing Scotland with the rest of the UK, NRS uses a wider measure of age-adjusted drug poisoning deaths.

This includes all deaths where the underlying cause was listed as mental and behavioural disorders due to psychoactive substance abuse or poisoning by drugs whether accidental, intentional, of unknown intent or as a result of assault.

The most recent comparable data from 2024 shows that Scotland had an age-adjusted death rate of 216 per million compared with 91 for England, 140 for Wales and 135 for Northern Ireland.

Catriona Matheson, professor of substance use at Stirling University, said the “deeply concerning” increase in deaths was being driven by significant changes in the drug market – including the growth of nitazenes.

She told BBC Radio Scotland Breakfast that their potency was unpredictable and that some could be 50 times stronger than heroin.

“People are not expecting that in the drugs that they’re taking,” she said.

“They may be buying what they think is heroin and in fact it may contain several other substances in it.”

Matheson said an increase in “polydrug use” in recent years had contributed to the problem and could prove to be lethal.