HEROIN USERS RELAPSE DESPITE NALTREXONE

Rapid detoxification of heroin addicts may not be as effective a treatment
as first thought, with many addicts relapsing into drug use, the Australian
Medical Association said yesterday.

Accelerated detoxification, using the drug naltrexone, has been promoted as
a "cure" for heroin addiction since 1997.

Naltrexone blocks the effects of heroin withdrawal that occurs about eight
to 12 hours after the last heroin use, with the patient under general or
light sedation.

But a study published yesterday in the latest edition of the Medical Journal
of Australia (MJA) found many patients started using heroin again and the
retention rate on maintenance programs was low.

The study was conducted by Dr James Bell and researchers at the National
Drug and Alcohol Research Centre's Langton centre in Sydney and the National
Centre for Epidemiology and Population Health in Canberra.

The researchers examined the success rate of naltrexone-accelerated
withdrawal under light sedation for 15 heroin users and for a similar number
seeking withdrawal from methadone at a hospital in Sydney.

But three months after treatment, 18 patients had returned to heroin use or
methadone maintenance and one had died from a heroin overdose.

The researchers said most studies of naltrexone maintenance had shown high
drop-out rates and high relapse rates into heroin use.

Professor Wayne Hall of the National Drug and Alcohol Research Centre at NSW
University and Dr Alex Wodak of the alcohol and drug service at St Vincent's
Hospital, said the media's enthusiasm for naltrexone-accelerated heroin
withdrawal had not been shared by many addiction specialists.

"No evidence has yet been presented to challenge the assumption that
naltrexone, however packaged, is at best modestly effective and at worst
unsafe, in management of unselected cases of opioid dependence," they said
in the MJA.