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By Jean West
The children's drug Ritalin has a more
potent effect on the brain than cocaine.
Using brain imaging, scientists have found
that, in pill form, Ritalin - taken by thousands of British
children and four million in the United States - occupies
more of the neural transporters responsible for the 'high'
experienced by addicts than smoked or injected
cocaine. The research may alarm parents whose children have
been prescribed Ritalin as a solution to Attention Deficit
Hyperactive Disorder.
The study was commissioned to understand
more about why Ritalin - which has the
same pharmacological profile as cocaine - is effective
in calming children and helping them concentrate, while cocaine
produces an intense 'high' and is powerfully addictive.
In oral form, Ritalin did not induce this
intense psychological 'hit'. But Dr Nora Volkow, psychiatrist
and imaging expert at Brookhaven National Laboratory, in Upton,
New York, who led the study, said that injected into the veins
as a liquid rather than taken as a pill, it produced a rush
that 'addicts like very much'.
Interviewed in last week's Journal of
the American Medical Association newsletter, she said: 'They
say it's like cocaine.'
Even in pill form, Ritalin blocked far
more of the brain transporters that affect mood change and
had a greater potency in
the brain than cocaine. Researchers were shocked
by this finding.
A normal dose administered to children
blocked 70 per cent of the dopamine transporters. 'The data
clearly show the notion
that Ritalin is a weak stimulant is completely incorrect,'
said Volkow. Cocaine is known to block around 50 per cent
of these transporters, leaving a surfeit of dopamine in the
system, which is responsible for the hit addicts crave.
But now it is known that Ritalin
blocks 20 percent more of these auto-receptors.
'I've been almost obsessed about trying
to understand [Ritalin] with imaging,' said Volkow. 'As a
psychiatrist I sometimes feel embarrassed [about the lack
of knowledge] because this is by far the drug we prescribe
most frequently to children.'
However, it was still not clear why a
drug that has been administered for more than 40 years was
not producing an army of addicted schoolchildren. Volkow and
her team concluded that this was due to the much slower process
of oral ingestion.
It takes around an hour for Ritalin in
pill form to raise dopamine levels in the brain. Smoked or
injected, cocaine does this in seconds.
Dr. Joanna Fowler, who worked with Volkow
on the project, said: 'All drugs that are abused by humans
release large quantities of dopamine. But dopamine is also
necessary for people to be able to pay attention and filter
out other distractions.'
But opponents of Ritalin, labeled a 'wonder
drug' and a 'chemical cosh', believe it may be addictive and
has dangerous side-effects. Moreover, many believe ADHD is
a fraudulent title for a non-existent condition once put down
to the exuberance of youth.
Professor Steve Baldwin, a child psychologist
from Teesside University, who died this year in the Selby
rail crash, campaigned against Ritalin. He pointed out similarities
between the drug and amphetamines as well as cocaine.
Mandy Smith of Banff in Scotland has a
son of eight who was prescribed Ritalin for nine months. 'I
am astonished the British Government have allowed this drug
to be prescribed,' she said. 'It can destroy people's lives.
My son was a changed person when he took Ritalin. He was suicidal
and depressed.'
Janice Hill, of the Overload Support Network,
a charity for parents of children with behavioral problems,
said: 'Now we have thousands of children in Scotland taking
a drug that is more potent than cocaine. What does it take
before the situation is thoroughly investigated?'
The
Observer September 9, 2001
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