Soaring drug deaths in Scotland have emerged as one of the country's starkest tragedies and biggest public health controversies over the past decade.

Former First Minister Nicola Sturgeon admitted in April 2021 that the Scottish Government "took our eye off the ball" as the crisis unfolded.

Reversing - or failing to reverse - the trend in fatal overdoses is now a key measure under which the SNP-led government will be judged.

After signs of a potential slowdown during 2021, the latest set of annual statistics due for publication on Tuesday - covering deaths during 2022 - will be closely scrutinised.

READ MORE: Leading charity slams lack of leadership over Scottish drug deaths 

The Herald:

What's happened to drug deaths?

Between 1996 and 2013, there was a steady rise in yearly drug misuse deaths in Scotland from 244 to 527.

This accelerated dramatically over the past decade, however, reaching a peak of 1,339 in 2020.

In 2021 - the most recent year for which statistics are available - the death toll dipped very slightly, to 1,330.

The Herald: Drug death numbers have soared in Scotland Drug death numbers have soared in Scotland (Image: NRS)

What are "drug-misuse" deaths?

National Records of Scotland, the body responsible for the statistics, includes any drug abuse or drug poisoning deaths which involved a "controlled" drug.

This could range from illegal drugs such as heroin to category C pharmaceuticals, such as the opioid-based painkiller tramadol, which may have been obtained on prescription or illicitly.

A fatal overdose caused solely by a non-controlled drug, such as paracetamol, would not be included.

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How does Scotland compare to UK and internationally?

In 2020, Scotland had a drug misuse death rate in of 245 per million people compared to 50 per million in England, 47 per million in Wales, and 96 per million in Northern Ireland.

Comparisons with Europe are based on a slightly different metric which restricts deaths to the 15-64 age group only. In addition the list of controlled drugs can differ between countries.

In 2020, Scotland's drug death rate was by far the highest in Europe: 327 per million compared to 85 per million in Norway, the second highest.

Globally, Scotland was second only to the United States, which recorded 277 drug deaths per million people (all age groups) in 2020.

The Herald:

Who is dying?

Nearly two thirds (65%) of drug deaths in Scotland in 2021 occurred in the 35 to 54 age group.

This age group is also the main driver for the increase in fatal overdoses over the past decade - up by roughly three-fold.

By 2021, the average age for someone suffering a drug misuse death was 44, compared to 32 in 2000.

Males were 2.4 times more likely than females to suffer a fatal overdose.

The deprivation gap has also widened. In 2001, people living in Scotland's poorest areas were 10 times more likely to suffer a fatal drug overdose; by 2021, the difference was 15 times.

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What drugs are implicated?

In 2021, 84% of drug misuse deaths involved opiates or opioids (such as heroin, morphine and methadone).

So-called "street benzos" (illegal supplies of benzodiazepines such as diazepam or etizolam) were also a growing problem. In 2021, they were involved in 918 drug deaths compared to 191 in 2015.

The Herald: Black market benzodiazepines have been linked to a growing number of drug deathsBlack market benzodiazepines have been linked to a growing number of drug deaths (Image: NRS)

More recently regulators have been flagging concerns over the growing trade in ultra-strong synthetic opioids, called nitazenes. 

In January, Public Health Scotland warned that the drugs - sometimes being missold in the form of counterfeit oxycodone tablets - "pose a substantial risk of overdose, hospitalisation and death".

Previously almost all heroin consumed in Europe came from Afghanistan, but a Taliban-imposed ban on poppy growing has also sparked fears that the market will be flooded with fentanyl instead - a synthetic opioid which is roughly 50 times stronger than natural heroin.