But it took years to get there. For Paul's mother Ann, it was less a sense of inevitability than of warnings ignored; urgings dismissed. Her efforts to persuade doctors and pharmacies she knew to be supplying him with too many drugs were not enough to halt his access.

For Paul and hundreds like him, the access was an "unintended consequence" of Australia's well-resourced health system, the head of clinical services at Victoria's Turning Point Drug and Alcohol Centre, Dr Matthew Frei, says.

According to data collated by the Australian Bureau of Statistics, the number of drug-induced deaths has been climbing steadily in Australia for a decade and now claims 7.5 lives per 100,000. Of the 1808 deaths in 2016, the majority were linked to benzodiazepines and oxycodone - tranquillisers and pain relief drugs commonly prescribed for anxiety, sleeping problems and physical injuries. Prescription rates for many of these medications has also increased in recent years, prompting some medical journals to warn of the emergence of a new, hidden population dependent on prescribed or over-the-counter medicines.

Ann had fought to be heard, to have her son heard. Almost seven years on from that night, the inquest into the death of Paul Fennessy came to a formal close. Coroner Margaret Hunter found the Weston Creek pharmacy had wrongly dispensed a double-dose of methadone. But she also found the hospital's decision not to detain Paul was "not unreasonable", "given they believed they had no mechanism available". Ann and her lawyer maintain Paul could have been involuntarily detained that day, but ultimately he was not. Coroner Hunter made two recommendations: the second, that all hospital staff have access to all mental health notes, was already the case. The first, that the territory government fully implement a real-time prescription monitoring system in the ACT.

The calls for such a system go back more than a decade. Coroners from around the country, indeed across the developed world, have urged governments to implement monitoring schemes nationally. In July last year, the federal government promised $16 million towards rolling out that regime. The ACT government, in the wake of the inquest report, has committed just over $700,000 for a local system.

But those amounts pale in comparison to the $30 million the Victorian government has promised, which also includes some wider services.

"All of those things seem such fundamental things that governments should do," Paul's uncle, Philip, says.

For the health system, the scheme would help stop doctors "prescribing blind", experts say. But a state or territory based system will not and has not stopped people crossing the border to access drugs. And while effective monitoring will identify people abusing prescription drugs, it won't make the health system better at treating them.

"That's where I think a lot of the hard work is," says Jennifer Pilgrim, a Victorian forensic pharmacologist and toxicologist. A lot of people who become addicted to prescriptions drugs are not trying to get a better high, she says. Rather, people misuse the drug to try to better treat their symptoms and pain, including from mental illness. The challenge, says Gabrielle Cooper, a professor of pharmacology at the University of Canberra, is that "we don't always have a substance that's going to give people relief".

Demand for both mental health and drug and alcohol services outstrips supply every day of the week. It has been years since Karralika, one of two main residential drug and alcohol rehabilitation programs in Canberra, a capital city with a booming population, received any new capital funding from the territory. Waiting lists of three to eight weeks for a bed show there is far greater demand than there is capacity.

High-need mental health patients are given priority in accessing mental health-run services. Others misusing drugs or alcohol, but who more often than not have underlying mental health issues, are referred to drug and alcohol services. But services like Karralika are only able to support people with low to moderate mental health needs. Some of these groups do slip through the cracks. "If you're not necessarily core business for mental health, you may be a bit too demanding for your local drug and alcohol service," Dr Frei says.

In Paul's case, professionals assessing him for suicide risk more often than not concluded he was not at risk, despite records showing he repeatedly presented with overdoses and possible intentions to self harm. "I don't think he was taken seriously, his mental health," Ann says. "He was dismissed as a substance user rather than looking at him as a person and doing really good assessments."

Teams in drug and alcohol services, and their counterparts in mental health, speak different languages, a cultural divide seen throughout the country. Bronwyn Hendry, from drug and alcohol service, Directions ACT, says: "We have to recognise that when people have severe substance use disorder, and certainly severe enough to be life threatening, is very likely that there's a mental illness as well."

The connection between mental health and drug abuse is well-established. The head of Karralika, Sharon Tuffin, estimates that about 80 per cent of the people who seek treatment with the program have an underlying mental illness.

But health staff also struggle with what to treat first when someone presents with both drug addiction and mental illness, rather than seeing the dual diagnosis as intertwined. But Ms Hendry says they know treating the conditions one after the other was less effective than treating them simultaneously. "We have to change so we are not treating people sequentially," she says.

Australia spends about $1.2 billion annually on drug and alcohol treatment, roughly one per cent of its total healthcare spending, according to a 2014 National Drug and Alcohol Research Centre report. If health care resources were distributed according to the weight of the burden of disease; in the case of drug and alcohol, 1.9 per cent, experts say it would justify doubling what is currently spent, to at least $2.5 billion. Such funding, Ann says, could help save people in the future.

"People have said, 'Oh it's about time you got over it, what are you going to do, do you think you've had enough of this, Ann?'" she says. "And I did say it to one person, which one of your kids would you not fight for?"

"Until you're in that position, you have no idea what that's like."

If this story raises concerns for you, contact Lifeline on 13 11 14.