The number of overdoses from prescription pain killers is on the rise, with 800 Australians dying per year, warn health experts.
They say the toll is highest in rural and regional areas, and many addicts are moving across state borders to get their preferred drug.
Dr Suzanne Neilsen said, from the National Drug and Alcohol Research Centre (NDARC) said there had been a particular increase in the number of pharmaceutical opioid-related deaths in the past decade.
"Some of the medications that we've been looking at include oxycontin, fentanyl, codeine, morphine — they're I guess more commonly prescribed opioids," she said.
Dr Neilsen said one problem was that not all regional areas had accredited prescribers or pharmacies that provided treatment.
Addiction specialist Dr Roger Brough, who works in regional Victoria, said his work had shifted from heroine drug use to prescription overuse in the past 15 years.
In one recent case, Dr Brough said a nurse collecting high-dosage prescription medication told him that she was being followed during her trips to the pharmacy.
"She was probably known in the community as a nurse, it made her very aware first-hand of the sort of practice we are aware do go on in pharmacies," he said.
Dr Brough said he knew of patients moving across borders to get as many drugs as possible.
"They have to travel significant distances to be relatively ensured of their anonymity — traveling to NSW, South Australia, Tasmania," he said.
Easier to go undetected, users say
In Campbelltown in south-west Sydney, one woman told the ABC that while she had never used illegal drugs in her life, she did take Xanax without a prescription.
She said the drug began to change her behaviour, to the extent that her family noticed.
"My sibling [said] that I was snapping at them all the time — and I don't fight with my brothers and sisters," she said.
"[They said] 'something's going on with you, are you on drugs?' I said no I'm not on drugs, I don't use drugs.
"But Xanax is prescription, medication pills.
"My boyfriend tried to tell me 'you're not prescribed it, therefore you're abusing it' — I'm like 'it doesn't matter, it's completely different'."
In a community where the drug ice is a big problem, she said Xanax was easier to get without being detected by authorities.
She said the worst thing police would do if they pulled a person over without a prescription bottle in their names, was take the bottle away.
"And then you'd just go get more. If you get done with pot or ice or anything, you get in serious trouble," she said.
She said she had already overdosed about four times on the prescription drug.
"I just took heaps of pills. Lots and lots of pills," she said.