Once-a-Day Concerta: Less Abuse Risk?
Researchers Say Time-Released Version of ADHD Drug May Have Less Appeal to Drug Abusers
March 9, 2006 - Surveys suggest that Ritalin abuse is a growing problem
among teens in the U.S., but there is increasing evidence that the risk of
abuse is much lower with newer, time-released versions of the stimulant most
commonly used to treat attention deficit hyperactivity disorder.
Brain imaging studies and blood tests conducted by researchers at
Massachusetts General Hospital showed that the widely prescribed once-a-day
ADHD drug Concerta acts differently in the body than the rapid-release form of
Ritalin, even though both drugs contain the same active ingredient -- the
As expected, the tests showed that the delayed-released drug took longer to
reach peak effective levels within the brain and body and the regulating
effects lasted longer than with the rapid-release version of the stimulant.
And adult study participants without ADHD who took the rapid-release form of
the stimulant were more likely to report feeling a pleasant effect from the
drug than participants who took the timed-release stimulant.
"We know that drugs that cause euphoria are potentially abusable, and
euphoria requires rapid delivery to the brain," says Thomas J. Spencer, MD,
who led the research team. "The ability to show that rate of brain delivery
may determine abuse potential is important to our understanding of the safety
of different formulations."
Different Types of Abuse
According to a nationwide study of drug abuse patterns among adolescents,
known as the Monitoring the Future Survey, Ritalin abuse among high-school
seniors doubled between 1999 and 2004, from 2.5% to 5.1%.
Spencer says some of this increase may be due more to misuse of the drugs by
people without ADHD who want to exploit their stimulant effect, rather than by
serious drug users looking to get high.
Serious abusers often crush the rapid-release form of the stimulant and then
snort it like cocaine to create a high. The long-acting stimulants have less
potential for this type of abuse, Spencer says.
"We can't really say what percentage of abusers are trying to get high
and how many may be taking the drug orally to stay up and cram for a test,"
The Role of Federal Regulators
All stimulants used to treat ADHD, including slow-release drugs, are
classified as schedule II controlled substances.
Researcher Joseph Biederman, MD, says if long-acting methylphenidates like
Concerta, Metadate CD, and Ritalin LA are proven to have a low potential for
abuse, federal regulators should make them more easily obtainable.
"In my opinion these are potentially much safer compounds," he
Biederman is chief of pediatric psychopharmacology research at Massachusetts
General Hospital and a professor of psychiatry at Harvard Medical School.
Drugs Can Still Be Manipulated
Nora D. Volkow, MD, conducted some of the first studies showing that rapid
delivery of drug stimulants like methylphenidate and cocaine is an important
key to producing the euphoric effects or high that drug abusers seek. She now
directs the National Institute on Drug Abuse.
Volkow agrees that the once-a-day, long-acting methylphenidate formulations
are likely to have a lower potential for abuse, especially by casual drug
users. But she says the drugs should not be made easier to get because they can
still be manipulated to produce a high.
"It is not that easy, but it can be done," she says. "My
perspective is that these drugs should not be easily accessible, because there
is definitely the potential for abuse."
Spencer says it isn't yet clear if the once-a-day oral methylphenidates are
being abused because they have only been commercially available for a few
"The final evidence as to whether they are less abusable will be the
data showing that they are being abused less," he says. "And we don't
have that yet."
The study by Spencer and colleagues is published in the March issue of the
American Journal of Psychiatry. It was funded by both the National
Institute for Mental Health and McNeil Pharmaceuticals, the manufacturer of