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Re: Ritilan - the next street drug of choice?
olcoon (olcoon@SKY.NET)
Sat, 31 Oct 1998 03:02:12 -0600
I got this off another list back in April, thought you all might be
interested. =20
Roy Evans I used to be an Eagle.....
ASM Troop 460
Kansas City, Mo. =20
=20
RESEARCHERS WORRY RITALIN MAY SPARK COCAINE HABIT
by Alison Motluk
=A9 1998 New Scientist
A conference this fall will focus on a drug regularly taken by millions of
American children that is similar in crucial ways to cocaine. Some experts
are studying whether it could encourage substance abuse in later life.
The drug is methylphenidate, better known as Ritalin. It is the leading
treatment for a neurological condition known as attention
deficit-hyperactivity disorder, or ADHD. The disorder prevents children -
mostly boys - from focusing their mental energies. Scientists have little
idea what causes the disorder. They believe it involves the failure of
certain receptors in the brain to respond to the neurotransmitter dopamine.
Ritalin has transformed the lives of ADHD children. It has become by far
the most popular drug for dealing with the condition, with a 90 percent
share of the market.
According to the Drug Enforcement Administration, production of Ritalin in
the United States increased almost fivefold from 1990 to 1995. Ritalin has
been around for more than 40 years, and was originally used to treat
narcolepsy, a sleeping illness. Its increased use is mainly because of the
rapid rise in the number of people diagnosed with ADHD, especially in the
United States. Some doctors claim that up to 5 percent of all boys and 2
percent of girls worldwide - and a large number of adults - suffer from the
condition. Outside the United States, doctors are more skeptical about
ADHD, but even those who believe Ritalin is being over-prescribed agree
that it is a genuine disorder and that Ritalin helps. But over the past
few years there have been growing concerns about its long-term effects.
Ritalin is a stimulant that works by making dopamine more available in the
brain. Its effects in the brain are very similar to those of cocaine, and
some researchers are warning that regularly giving children a cocaine-like
substance might prime them for drug abuse later in life.
Fears on agenda
They also say that children on Ritalin are more likely to smoke. Fears such
as these have put Ritalin firmly on the agenda for the National Institutes
of Health conference on
ADHD, scheduled for November.
Concerns about Ritalin began to emerge in 1995, with a study in the
Archives of General Psychiatry titled ``is methylphenidate like cocaine?''
The paper concluded that it was. Its lead author, Nora Volkow, director of
nuclear medicine at the Brookhaven National Laboratory in Upton, N.Y.,
looked into where and how quickly Ritalin acts in the human brain. In
Volkow's study, eight healthy male volunteers were injected with the drug.
Their scans were then compared with those of subjects in previous studies
who had been injected with cocaine. The authors reported that the
distribution of Ritalin in the human brain was ``almost identical to that
of cocaine.'' The drugs' effects also peaked at almost the same time -
between four and 10 minutes in the case of Ritalin, and two and eight
minutes for cocaine. Even the highs were similar.
Very similar drugs
``We've given it to cocaine users, and they say it's almost
indistinguishable,'' Volkow says. The only significant difference was that
Ritalin took over four times as long - 90
minutes - to leave the body. Volkow stresses, however, that taking a
stimulant orally is very different from injecting or snorting it.
Intravenous caffeine also resembles cocaine, she points out. Her paper
warned that similarities between cocaine and Ritalin ``should not be used
as an argument against the use of methylphenidate.'' And she admits that
there is no evidence of a link between Ritalin use and cocaine abuse. But
she adds: ``We do have evidence that if we don't treat them, then they will
turn to self-medication.'' She says that 10 percent to 30 percent of
cocaine abusers take cocaine because they have ADHD. ``When we give them
Ritalin, the cocaine problem is resolved,'' she says. Volkow's results came
on top of earlier animal experiments suggesting that prolonged exposure to
some stimulants made rats more likely to become addicted to cocaine.
Study of rats
One such study by Susan Schenk, a psychopharmacologist at Texas A&M
University in College Station, involved rats that pressed a lever to give
themselves cocaine. The experiment showed that rats given amphetamines for
nine consecutive days were more likely to give themselves cocaine than rats
that had been given saline solution. The fear is that, like amphetamines,
Ritalin primes the brain so that any later use of cocaine has a bigger
effect than it would otherwise. If so, Ritalin may make people more likely
to abuse cocaine or other stimulants, rather than experiment with them once
or twice. To find out whether her findings had implications for children
taking Ritalin, Schenk teamed up with Nadine Lambert, a developmental
psychologist at the University of California at Berkeley. Lambert followed
the progress of 5,000 children with ADHD in the San Francisco area from
adolescence into adulthood to discover whether the drug has any effect on
tobacco, alcohol and illicit drug use in later life. In a paper to be
published in October in the Journal of Learning Disabilities, Lambert
claims that children who take Ritalin are more likely to smoke as adults.
Taste for cocaine
Other data, which Schenk presented at a meeting held by the DEA in December
1996 and are being revised for publication, suggest that they are no more
likely to abuse alcohol or marijuana, but are three times more likely to
develop a taste for cocaine. Not everyone is convinced.
Alan Zametkin, a psychiatrist at the National Institute of Mental Health
near Washington, D.C., says that the team's research design was flawed
because the subjects were not assigned at random. Those sufferers on
medication were probably more severe cases than those who were not, he
says. Schenk admits that there are uncertainties in the team's
study, but points out that whether the children were treated had little to
do with the severity of their condition. For instance, those not on
medication may have had parents who were against the use of drugs such as
Ritalin. Another attempt to monitor children taking Ritalin into early
adulthood supports Zametkin's skepticism.
Another study
Lily Hechtman, a psychiatrist at the Montreal Children's Hospital, looked
at people who had taken Ritalin for three to five years, and compared them
with people who were not
hyperactive and people who had been diagnosed with AHD but not given the
drug. She found no significant differences in patterns of substance abuse
among the three groups. Zametkin goes further. He believes that sufferers
who are given Ritalin are less - not more - likely to abuse drugs later in
life.
``My theory is that stimulant use allows kids to be more successful and
therefore they develop fewer anti-social behaviors,'' Zametkin says. ``So
it's less likely they'll become
drug addicts.'' Schenk, too, accepts that Ritalin is a useful drug. In a
cost-benefit analysis, she says, any side effects would probably pale in
comparison to the good it does. But that does not mean that you should not
look for them, she says. ``You still have to know what the costs are.''
Articles and reports about Ritalin can be found at The
Center for the Study of Psychiatry and Psychology.
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