MEDICINE MAY ENCOURAGE COCAINE USE

Concern is growing that a drug given to millions of hyperactive children
worldwide may prime their brains for drug abuse later in life.

Some researchers in the United States fear that the leading treatment for
attention deficit hyperactivity disorder (ADHD), methylphenidate marketed
as Ritalin, affects the brain like cocaine.

As a result, they suggest that cocaine may have a bigger impact on people
who were treated with the drug, thereby increasing the likelihood they will
"develop a taste for cocaine", New Scientist magazine reported at the
weekend.

In Australia, the National Health and Medical Research Council has
estimated that between 2 and 6 per cent of children, mostly boys, are
affected by the disorder. Sufferers often find it difficult to concentrate
and are prone to fidgeting, impulsive movements and clumsiness.

According to New Scientist, animal experiments and a study of just how and
where Ritalin works in the human brain support the claim that it may
encourage cocaine use.

A long-term study of 5000 Californian adolescents with the disorder found
that, as adults, those treated with Ritalin were three times more likely to
use cocaine - although they were no more likely to abuse alcohol or
marijuana - than those who did not take the medication.

The research was conducted by a pharmacologist, Dr Susan Schenk, at Texas A
& M University and a psychologist, Dr Nadine Lambert, of the University of
California.

Australian experts greeted the suggestion that Ritalin may be linked to
cocaine abuse with caution.

Although she said the possibility "certainly requires further work",
University of New South Wales Associate Professor Florence Levy, head of
the Avoca Clinic at the Prince of Wales Department of Child and Adolescent
Psychiatry, said that for many children the benefits of Ritalin outweighed
the potential risks.

Dr Christopher Green, director of the Child Development Unit at the New
Children's Hospital, went further, pointing to a study of high school
students in the US which found those treated with the medication were less
likely to drop out of school and abuse drugs than those who did not receive
treatment.