The 24-year-old was so sick that in the final year of his life he was barely able to leave his bedroom.

One night, as she slept down the hall of his house, she suddenly awoke. Thump.

Sally found Sam on all fours, his head against the wall, barely breathing in his room. He was rushed to hospital, only to be discharged hours later.

The very next day she heard another loud noise and found him collapsed again. This time he wasn't breathing at all.

Sally administered CPR until the ambulance arrived. He was again released from hospital soon after.

Sam wasn't ill from cancer or heart disease. He had a dual diagnosis of mental illness from trauma and drug addiction.

"Had it been cancer or heart problems, he wouldn't have been discharged if he almost lost his life," Sally says. "He had an illness and he was treated differently to anyone else."

Six months later, in June last year, Sally had been staying at Sam's place for three nights but needed to go home for a night.

She never saw her son alive again.

Sam is one of 477 Victorians who died of a drug overdose in 2016, statistics released by the Coroner's Court on Wednesday show.

The number is expected to rise to 500 as investigations are finalised.

Victoria's overdose rate has been steadily rising since 2010, up almost 40 per cent from 342 to 477.

MDMA deaths have more than doubled in a year, up from five to 11. These deaths do not include the three deaths that resulted from a bad batch traded in Chapel Street in January this year.

Meanwhile, overdose deaths where methamphetamine, or ice, was a contributing drug have soared from 72 to 116 in the same time, a 40 per cent increase.

But heroin is still the bigger killer among illegal drugs - overdoses in this categoy are up from 227 to 257.

Many overdoses cannot be traced back to a single source - 70 per cent of fatal overdoses involved a cocktail of drugs.

State Coroner Judge Sara Hinchey has written an opinion piece in Wednesday's Age, saying she hopes the release of the data will help Victoria to save lives.

Her recommendations include more long-term involuntary and voluntary treatment beds, more dual diagnosis treatment, better education and prescription drug monitoring.

Sam Biondo, chief executive of the Victorian Drug and Alcohol Association, said drug rehabilitation centres were not meeting demand, while a safe injecting room and pill testing were needed to combat the growing problem.

"Law and order is not going to work. It's not working. And it will never work," he said.

"It's so frustrating to see things we could do to save lives and we don't because of the political advantage of appearing to look tough on an issue rather than providing a solution to the problem."

A spokeswoman for Mental Health Minister Martin Foley said the data was concerning.

She said the government had increased rehab beds and slated funding for a new rehab in the Grampians and a day treatment program for up to 500 people a year.

"We will also continue to lobby the Turnbull government to properly regulate the private and government sector to protect and support those seeking help," she said.

The spokeswoman said the government had no plans to set up a safe injecting room or to introduce pill testing but would carefully consider the Coroner's recommendations.

Sally Morrison believes that if Sam had access to a safe injecting room or a long-term rehab without a long waiting list he would still be alive today.

"My three sons have each been to more funerals than me, mostly young people who have suicided because of mental illness or died from drug overdoses," she wrote to the Coroner after Sam's death.

"Surely all the lives lost are due to a system that is failing. From a loving mother who misses and cries for her youngest son every minute of every day."

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