Drug and alcohol abuse costs NI £1bn a year
The costs of substance misuse in Northern Ireland is an "unsustainable financial burden", an Audit Office report has said.
The Department of Health said it spends over £1bn dealing with drug and alcohol misuse every year and it is a key priority for the minister.
The report said substance misuse causes a wide range of harm to individuals, their families and wider society.
It estimated that alcohol abuse costs the public purse up to £900m a year.
It added that every day more than 200 hospital beds are occupied by patients with drug or alcohol related problems.
According to the auditor general these figures paint a worrying picture of a growing problem.
But he says despite some cost effective initiatives, the lack of reliable information from the Department of Health on outcomes for those seeking help means its impossible to determine whether public spending on addiction services provides value for money.
Health Minister Robin Swann said reducing the harms caused by substance use was "a key priority for my department and for me."
"I note many of the issues raised were already identified in the review of our current substance misuse strategy that was published by my department last year," he said.
He added: "Work is under way to develop a new substance use strategy for Northern Ireland.
"I plan to bring forward a formal consultation on this strategy in the near future and the Northern Ireland Audit Office report will inform this process and the new strategy will seek to address the issues raised."
Alex Bunting of Addiction NI told the BBC the report provides a "very honest reflection of the current issues" in Northern Ireland.
He said the consultation cannot become "a missed opportunity" to shape future services.
While addiction costs £1bn annually, it is being addressed "with a strategy that is resourced with about £8m a year," he said.
He added: "I think the crucial thing from our perspective is we have to get this one right, we cannot let this go any further.
"We are sitting as the region in the UK with some of the worst figures but also with the least amount of investment".