That fall in approvals - which doctors need before filled prescriptions, fell in Canberra after changes to the territory's old paper-based prescription monitoring system, including a weekly digital update on prescriptions filled and data monitoring for 'red flags'.

Those changes have seen pharmacists go from faxing hard copy lists of the controlled drugs - from codeine to oxycodone - once a month to ACT Health - to a weekly digital data transfer.

The Canberra Times understands a decision was made to institute a fully operational real-time monitoring system about three years ago, but was not instituted at the time, in the hope a national system would be running.

But in the absence of the national real-time prescription monitoring system, ACT Health modelling a similar program on the only such operational system in the country in Tasmania.

The major change to the old system, ACT Chief Health Officer Paul Kelly said, was the creation of 'red flags' on unusual prescribing or dispensing behaviour by doctors and pharmacists, and on individuals obtaining those scripts, in Canberra.

But it is not yet up to the standard of a "real-time" prescription monitoring system that numerous health groups have repeatedly urged be implemented nationally.

Dr Kelly said the improvements made in April 2016 had help cut the number of application approvals for doctors to issue Schedule 8 (S8) 'controlled drugs' prescriptions fell from 2000 a month to 1500 every four weeks, over the 10 months since.

The changes are part of the local response to a growing worldwide problem with prescription opioid abuse - a study by the National Drug and Alcohol Research Centre released last June showed some 394 accidental drug deaths in Australia were due to the category of powerful prescription pain killers.

But despite an ACT coronial recommendation made in November last year for the 'real-time' system to be set up in Canberra - including an interface for pharmacists and GPs to use to see if an individual patient is obtaining too many S8 prescriptions - that function is not yet active.

Dr Kelly said the new alert functions had helped to cut the total number of scripts issued, but also helped identify GPs and pharmacists who may be over-prescribing the medicines, as well as break-up at least one interstate criminal syndicate trying to obtain such drugs to sell on the black market.

He said the number of S8 prescriptions being filled in the ACT had doubled over a five year period - from 12,000 in 2010 to 24,000 in 2015 - before the new alert system was running.

But Dr Kelly said there remained weaknesses, as it only covered S8 drugs, and not most of the benzodiazepine family of drugs - also known for their higher likelihood of abuse.

While it has had administrative teething problems, Pharmacy Guild of Australia ACT president Amanda Galbraith said it meant pharmacists could now simply send the raw data from their computers to ACT Health once a week, instead of a monthly download and fax.

But she said ideally the system would be real-time, so both pharmacists and GPs would be able to see how many prescriptions had been issued and filled for each individual patient, before taking action.

"I think it's improved the system, but what we don't want is patients who are on an opioid for a particular condition missing out, then it becomes a problem," she said.

"We want to make sure when it's clinically required, we can supply the right dosage for the patient, but not for other purposes."

Ms Galbraith said she and others would also support widening the application of the monitoring to other drug categories, and even potentially all prescription-only drugs, but that such an extension could be years' away.

Correction: This article previously incorrectly stated that the monitoring programs resulted in a 25 per cent fall in S8 prescriptions being issued in the ACT. ACT Health has clarified there was no such fall in prescriptions issued, rather the fall was in "applications for approvals" to issue prescriptions.