Politicians have clashed over the use of heroin substitute methadone to treat recovering drug addicts.
The Scottish Government insists the treatment is useful as part of its Road to Recovery strategy. But Labour argues that addicts can be "stranded" on the substance without clear help to get clean.
In a debate at the Scottish Parliament, Community Safety Minister Roseanna Cunningham said: "Does methadone reduce drug-related deaths, blood-borne viruses and crime? We know it does. Does it stabilise lives? Yes, it does.
"But methadone is only one of a number of treatment options available. We are clear it can be effective but only as a component in a package of care, treatment and recovery."
Of the 19,000 drug treatments started in 2011-12, less than one-fifth were for prescribed drugs including methadone. "There is an assumption, a tendency, to assume out there that everybody is on methadone, and that simply is not true," she said. Of the 584 drug-related deaths last year, 14 may have been "wholly attributable" to methadone, she told MSPs.
Labour MSP Jenny Marra said the Government's drug strategy is unravelling. The total number of drug-related deaths increased by one-fifth on the previous year, she said. "While we recognise the advantages that methadone brings as one part of a comprehensive drugs strategy, we need to know that public money is being spent to do more than simply strand addicts in the system. That won't let all of them recover," she said.
Figures obtained by Labour show the cost to the taxpayer of funding methadone treatment is £36 million a year. Of that, locally negotiated rates create different costs across Scotland. "We don't believe this is fair, and we don't believe the Scottish people do either," she said.
Conservative MSP Annabel Goldie said the polarisation of the debate on methadone prescribing is unhelpful. "I accept that, depending on the individual, methadone may provide a bridge from the chaos of illegal using to a more stable existence.
"I do consider sensationalist articles in tabloid newspapers unhelpful. I also consider it unfortunate, particularly when the Road to Recovery anticipates a range of options, if someone seeking help who did not want to be prescribed methadone was given no alternative."
Liberal Democrat leader Willie Rennie said: "This is about the health professionals choosing what is the right way to proceed. It is not for politicians to decide which treatment can or cannot be used. Methadone is part of the solution and not part of the problem. We need to be very careful when we demonise families and we demonise the methadone programme."