HEROIN addicts could be treated with a painkiller which costs half as much as methadone, scientists said today.

The results of their study could have major implications for treatment programmes for drug users.

The study, the first of its kind, assessed 235 people requiring treatment for opiate dependency in Edinburgh over three-and-a-half years.

The research, by scientists at Edinburgh and Napier universities in Scotland and Adelaide University in Australia, found the prescription painkiller dihydrocodeine was just as effective as methadone in helping drug users kick the habit.

While methadone treatment can cost almost GBP1500 a year per patient, dihydrocodeine costs about GBP713.

It is also covered by less stringent regulations because it is not as toxic and is less likely to cause fatal overdoses.

Dihydrocodeine has been used for years to treat drug users and often is preferred in situations where methadone is seen as hazardous, such as police custody or prison.

However, its effectiveness had never been tested before.

Dr Roy Robertson of Edinburgh University, the study's main author, said: "Heroin addiction is a chronic condition requiring long-term medication. Just as with other chronic conditions, such as diabetes or arthritis, there should be a number of treatments so that doctors and nurses can tailor medication to the needs of each patient.

"Dihydrocodeine offers an alternative for those who can't tolerate methadone, or find it hard to deal with the stigma of having to take their dose - sometimes every day in a pharmacy. It is also cheaper."

The results of the study, funded by the Chief Scientist Office, are published in the current edition of the journal Addiction.