Prescription opioids, such as oxycodone and codeine are involved in most accidental drug deaths and more people are overdosing on anxiety and insomnia drugs.

Sleeping pills and anti-anxiety drugs have become the nation's "silent killers", with the number of people dying from the prescription drugs more than doubling in a decade.

That's the warning in a new report that found five people a day are now dying from a drug overdose, with middle-aged people the most likely victims.

The total number of drug-related deaths hit a 20-year high of 2177 in 2016, with accidental overdoses making up more than three quarters of cases, the Penington Institute's Annual Overdose Report says.

While prescription opioids, such as oxycodone and codeine, were to blame for most accidental drug deaths, the number of people overdosing on benzodiazepines prescribed to treat anxiety and sleep disorders has risen dramatically.

Benzodiazepine-related deaths were fairly stable at around 200 a year between 2001 and 2007, but that has soared to more than 600 since 2013.

The Penington Institute's chief executive John Ryan says benzodiazepines are "silent killers" that have slipped under the radar.

"People frequently use these drugs during a time of peak stress," he said as the report was released on Tuesday.

"Commonly used drugs like Temazepam used to help people sleep and Valium used for anxiety and sleep are involved in far too many accidental drug overdoses."

Mr Ryan expressed alarm at the rising number of overdoses from heroin and fentanyl, a synthetic opioid painkiller that's been blamed for driving a dramatic rise in overdose deaths in the United States.

The report found that the number of accidental deaths from synthetic opioids fentanyl, pethidine and tramadol totalled 997 between 2012 and 2016, nine times more than the 94 deaths recorded a decade earlier.

Mr Ryan said fentanyl overdoses were "enormous cause for alarm" and called on the federal government to review how it was prescribed.

Heroin-related deaths have also more than quadrupled in a decade, rising from 73 in 2006 to 362 in 2016 amid a sharp rise in the number of women overdosing on the illicit drug.

Out of all the drug-related deaths, 30-59 year olds made up nearly 70 per cent of cases in 2016.

Those aged 40 to 49 were the most likely to die, with prescription opioids and benzodiazepines the most common drugs involved.

Mr Ryan said the report's findings suggested that Australia's increasing overdose mortality rate puts it in line with the US, Canada and Britain.

He called on the government to increase the availability of drug treatments and set up a Productivity Commission review of current drug policy.