(Corrects to replace "methadone" with "mephedrone" in paragraph 11)
LONDON (Reuters) - The government said on Friday it was considering withdrawing benefits from those with drug or alcohol problems who refused to seek treatment.
It also planned to introduce temporary bans on "legal highs" that could be harmful to users.
As part of a consultation on a new drug strategy, the Home Office has put forward the idea that the benefit system should be used to help addicts overcome their dependency and get back to work.
Those who sought treatment for their addiction would be exempted from seeking work and could still receive welfare benefits. However those who did not seek help could face "some form of financial benefit sanction."
"The government is determined to prevent drug use and strengthen enforcement against supply," a Home Office spokesman said.
"That's why we are asking experts for their views on a range of issues so that users are strongly encouraged to address their dependency."
A report by the Social Services Advisory Committee in May said there was little evidence that sanctions would have any impact on the behavior of addicts.
It also warned that it might drive people from work and lead them to turn to crime and prostitution.
"We seriously question both the fairness and the effectiveness of actually using the stick of compulsion, benefit sanctions, to link a requirement to undergo medical treatment with a condition of receipt of benefit," Martin Barnes, chief executive of the charity DrugScope, told BBC radio.
On legal highs, a proposed new law will allow authorities to react quickly as new substances emerge, with 12-month bans while experts assess the drugs.
The move reflects public concern over the effects of legal highs such as the drug mephedrone which was banned in April.
"The drugs market is changing and we need to adapt current laws to allow us to act more quickly," Crime Prevention Minister James Brokenshire said in a statement.
"The temporary ban allows us to act straight away to stop new substances gaining a foothold in the market and help us tackle unscrupulous drug dealers trying to get round the law by peddling dangerous chemicals to young people," he said.
Under the planned legislation, authorities would be able to ban substances temporarily following an initial consideration by the Advisory Council on the Misuse of Drugs (ACMD).
The ACMD would then carry out a comprehensive review of the substance and advise whether it should be permanently banned.
Police would be able to confiscate suspect substances and the UK Border Agency could seize shipments entering the country.
The penalty for supplying a banned drug would be a maximum of 14 years in prison and an unlimited fine.
Possession of a temporarily banned substance for personal use would not be a criminal offence "to prevent the unnecessary criminalisation of young people," the government said.
Subject to parliamentary approval, the system of temporary bans is expected to be introduced by the end of next year.