Maintenance treatment with heroin is appropriate for heroin misusers under certain circumstances, argue Jürgen Rehm from the Centre for Addiction and Mental Health in Toronto and Benedikt Fischer from the University of Victoria, British Columbia.
They point to trials in Switzerland, the Netherlands and Germany, which found heroin assisted maintenance treatment feasible and effective for those resistant to treatment. They also found it to be cost effective compared with methadone maintenance treatment.
In the UK, heroin has also been a treatment option for heroin misusers for several decades, but the practice remains controversial.
"So, if maintenance treatment is generally justifiable, why should heroin not be used as one such pharmacological agent?" they ask.
One reason that has been cited is safety, both for the patient and for the general public. Yet results from the Swiss studies show that mortality among patients in heroin assisted maintenance programmes is low, and lower than for patients in other maintenance programmes.
But Neil McKeganey, Professor of Drug Misuse Research at the University of Glasgow argues that prescribing heroin to heroin addicts is treating the effects of misuse not the addiction.
The evidence in relation to heroin prescribing is far from conclusive, he says, while the cost of treating an addict with heroin is estimated to be three to four times that of treating an addict with methadone.
Prescribing heroin to heroin addicts is also a risky strategy, which could lead to massive pressure on doctors to prescribe increasing amounts of the drug.
Research has shown that with the right services in place it is possible to do more than simply stabilise addicts' continued drug use through the prescribing route, writes McKeganey. For example, a Scottish study found 29.4% of addicts who received residential rehabilitation were abstinent for at least 90 days compared with only 3.4% receiving methadone maintenance.