Research which said it is possible to live normally while regularly taking heroin has prompted a fierce debate.
Only a small number of those surveyed regularly injected heroin
The Glasgow Caledonian University study of 126 users of the class A drug found many were holding down normal jobs and relationships and passing exams.
The report said heroin could be taken in a controlled way for a period.
But drugs worker Peter Anderson and Alistair Ramsay of Scotland Against Drugs said the research was sending out the wrong messages.
Mr Ramsay said: "Anyone reading this who thinks they can take heroin safely would be wrong.
"In Scotland we have 55,800 heroin users who are clearly unable to function as normal so it cannot be assumed that the findings have universal application.
"The chances are the vast majority of those who start taking heroin are not going to be able to function and rather, they will develop major problems which require to be funded by the public purse."
However, Lord Victor Adebowale, the chief executive of specialist alcohol and drug organisation Turning Point, said the report was not saying that heroin was safe.
He explained: "It says that if you have a job, if you have a house, an income, are well educated and have a health system to support you, it's possible to survive an addiction to a pretty serious substance.
"Most people don't have this and have mental health challenges as well as a heroin problem."
At first minister's questions on Thursday, Jack McConnell said the Scottish Executive would do everything to tackle heroin addiction.
However, ministers have consistently ruled out the medical prescription of the drug.
Ministers also stressed that heroin was an illegal drug which "ruins lives and damages communities".
The report's author, Dr David Shewan, agreed that heroin was not a safe drug.
Researchers stressed that heroin is not a safe drug
He said the concept of controlled drug use was a "largely unexplored" area of research and warned that the results should be treated with caution.
The doctor added: "However, this study shows that the chemical properties of specific substances, including heroin, should not be assumed to inevitably lead to addictive and destructive patterns of drug use.
"Drug research should incorporate this previously hidden population to more fully inform theory and practice.
"Psychological and social factors have to be taken into account when looking at how to deal with any form of addiction, including heroin addiction."
Edinburgh-based outreach work Mr Anderson is a former drug addict who said heroin use and heroin injecting in Scotland is an immense problem which is getting worse.
He added: "Every day, unfortunately, men and women are dying in the UK from heroin overdoses and that is the context that we cannot forget."
The research has also sparked criticism in the way it was carried out.
The drug users were not interviewed personally, only through an intermediary.
However, the researchers said it was important to maintain trust and safeguard identities.
The work by Dr Shewan and his colleague Phil Dargarno was funded by the Chief Scientist Office.
The 126 people studied in Glasgow had been taking heroin for an average of seven years and were not receiving treatment for their drug use.
Most of those involved in the study were in a relationship and a third had children.
More than half reported a negative effect on jobs or education
In contrast to those receiving treatment for heroin use, three quarters of the sample group were employed and a third were placed at the top end of the job sector.
Some 64% of those surveyed had continued in education after secondary school, and 11% were in full-time higher education at the time of the research.
Unemployed people accounted for 15% of the group, and only 5% had no educational qualifications.
The study found that some heroin users could maintain occupations and achieve educational qualifications which were comparable with the general UK population - and were considerably higher than normally found in heroin research.
In the first phase of the study 30% of those involved reported drug-related health problems, although most did not require medical treatment.
Only a handful of those surveyed said they regularly injected heroin.
The group seemed reasonably satisfied with their level of physical health, with almost 48% describing their health as good and just 7% describing it as bad or fairly bad.
Just 15% of the participants reported that their heroin use had been associated with family problems, only one blamed the drug for the break-up of a long-term relationship and nobody's child had been taken into care.
While 60% reported a negative effect on their employment or education, only two people said drug misuse had cost them their jobs.
By the end of the study six participants had begun specialist drug treatment.