Methylphenidate (Ritalin)
Methylphenidate is a medication prescribed for individuals
(usually children) who have an abnormally high level of activity
or attention-deficit hyperactivity disorder (ADHD). According
to the National Institute of Mental Health, about 3 to 5 percent
of the general population has the disorder, which is characterized
by agitated behavior and an inability to focus on tasks. Methylphenidate
also is occasionally prescribed for treating narcolepsy.
Health Effects
Methylphenidate is a central nervous system (CNS) stimulant.
It has effects similar to, but more potent than, caffeine
and less potent than amphetamines. It has a notably calming
effect on hyperactive children and a "focusing"
effect on those with ADHD.
Recent research1 at Brookhaven National Laboratory may begin
to explain how methylphenidate helps people with ADHD. The
researchers used positron emission tomography (PET - a noninvasive
brain scan) to confirm that administering normal therapeutic
doses of methylphenidate to healthy, adult men increased their
dopamine levels. The researchers speculate that methylphenidate
amplifies the release of dopamine, a neurotransmitter, thereby
improving attention and focus in individuals who have dopamine
signals that are weak, such as individuals with ADHD.
When taken as prescribed, methylphenidate is a valuable medicine.
Research shows that people with ADHD do not become addicted
to stimulant medications when taken in the form prescribed
and at treatment dosages.2 Another study found that ADHD boys
treated with stimulants such as methylphenidate are significantly
less likely to abuse drugs and alcohol when they are older
than are non-treated ADHD boys.3
Because of its stimulant properties, however, in recent years
there have been reports of abuse of methylphenidate by people
for whom it is not a medication. Some individuals abuse it
for its stimulant effects: appetite suppression, wakefulness,
increased focus/attentiveness, and euphoria. When abused,
the tablets are either taken orally or crushed and snorted.
Some abusers dissolve the tablets in water and inject the
mixture - complications can arise from this because insoluble
fillers in the tablets can block small blood vessels.
Trends in Ritalin Abuse
At their June 2000 meeting, members of NIDA's Community Epidemiology
Work Group (CEWG)* shared the following information.
- The abuse of methylphenidate has been reported in Baltimore,
mostly among middle and high schools students; Boston, especially
among middle and upper-middle class communities; Detroit;
Minneapolis/St. Paul; Phoenix; and Texas.
- When abused, methylphenidate tablets are often used orally
or crushed and used intranasally.
- In 1999, 165 methylphenidate-related poison calls were made
in Detroit; 419 were reported in Texas, with 114 of those
involving intentional misuse or abuse.
- On Chicago's South Side, some users inject methylphenidate
(this is referred to as "west coast"). Also, some
mix it with heroin (a "speedball") or in combination
with both cocaine and heroin for a more potent effect.
Because stimulant medicines such as methylphenidate do have
potential for abuse, the U.S. Drug Enforcement Administration
(DEA) has placed stringent, Schedule II controls on their
manufacture, distribution, and prescription. For example,
DEA requires special licenses for these activities, and prescription
refills are not allowed. States may impose further regulations,
such as limiting the number of dosage units per prescription.
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For more information on treating ADHD, please call the National
Institute of Mental Health, National Institutes of Health,
at 301-443-4513 or visit their Internet address at www.nimh.nih.gov.
* This fact sheet highlights information from the June 2000
meeting of NIDA's Community Epidemiology Work Group (CEWG).
CEWG members meet twice yearly to share emerging trends in
drug abuse for 21 major U.S. metropolitan areas. CEWG reports
are on NIDA's website at www.drugabuse.gov.
1 Nora Volkow, et al., Therapeutic Doses of Oral Methylphenidate
Significantly Increase Extracellular Dopamine in the Human
Brain, The Journal of Neuroscience, 2001, 21:RC121:1-5.
2 Nora Volkow, et al., Dopamine Transporter Occupancies in
the Human Brain Induced by Therapeutic Doses of Oral Methylphenidate,
Am J Psychiatry 155:1325-1331, October 1998.
3 Joseph Biederman, et al., Pharmacotherapy of Attention-deficit
Hyperactivity Disorder Reduces Risk for Substance Use Disorder,
Pediatrics 1999 104:e20.
Source: National Institute on Drug Abuse
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