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Ecstasy Information
ecstasy
addiction
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MDMA
users may encounter problems similar to those experienced by amphetamine and
cocaine users, including addiction. In addition to its rewarding effects,
MDMA's psychological effects can include confusion, depression, sleep problems,
anxiety, and paranoia during, and sometimes weeks after, taking the drug.
Physical effects can include muscle tension, involuntary teeth-clenching,
nausea, blurred vision, faintness, and chills or sweating.
Increases in heart rate and blood pressure are a special risk for
people with circulatory or heart disease. MDMA-related fatalities at raves have
been reported. The stimulant effects of the drug, which enable the user to
dance for extended periods, combined with the hot, crowded conditions usually
found at raves can lead to dehydration, hyperthermia, and heart or kidney
failure. MDMA use damages brain serotonin neurons. Serotonin is thought to play
a role in regulating mood, memory, sleep, and appetite. Recent research
indicates heavy MDMA use causes persistent memory problems in humans.
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Long-term brain
injury from use of ecstasy
The
designer drug ecstasy, or MDMA, causes long-lasting damage to brain areas that
are critical for thought and memory, according to new research findings in the
June 15 issue of The Journal of Neuroscience. In an experiment with red
squirrel monkeys, researchers at The Johns Hopkins University demonstrated that
4 days of exposure to the drug caused damage that persisted 6 to 7 years later.
These findings help to validate previous research by the Hopkins team in
humans, showing that people who had taken MDMA scored lower on memory tests.
"The serotonin system, which is compromised by MDMA,
is fundamental to the brain's integration of information and emotion," says Dr.
Alan I. Leshner, director of the National Institute on Drug Abuse (NIDA),
National Institutes of Health, which funded the research. "At the very least,
people who take MDMA, even just a few times, are risking long-term, perhaps
permanent, problems with learning and memory."
The
researchers found that the nerve cells (neurons) damaged by MDMA are those that
use the chemical serotonin to communicate with other neurons. The Hopkins team
had also previously conducted brain imaging research in human MDMA users, in
collaboration with the National Institute of Mental Health, which showed
extensive damage to serotonin neurons.
MDMA
(3,4-methylenedioxymethamphetamine) has a stimulant effect, causing similar
euphoria and increased alertness as cocaine and amphetamine. It also causes
mescaline-like psychedelic effects. First used in the 1980s, MDMA is often
taken at large, all-night "rave" parties.
In this
new study, the Hopkins researchers administered either MDMA or salt water to
the monkeys twice a day for 4 days. After 2 weeks, the scientists examined the
brains of half of the monkeys. Then, after 6 to 7 years, the brains of the
remaining monkeys were examined, along with age-matched controls.
In the brains of the monkeys examined soon after the
2-week period, Dr. George Ricaurte and his colleagues found that MDMA caused
more damage to serotonin neurons in some parts of the brain than in others.
Areas particularly affected were the neocortex (the outer part of the brain
where conscious thought occurs) and the hippocampus (which plays a key role in
forming long-term memories).
This
damage was also apparent, although to a lesser extent, in the brains of monkeys
who had received MDMA during the same 2-week period but who had received no
MDMA for 6 to 7 years. In contrast, no damage was noticeable in the brains of
those who had received salt water.
"Some
recovery of serotonin neurons was apparent in the brains of the monkeys given
MDMA 6 to 7 years previously," says Dr. Ricaurte, "but this recovery occurred
only in certain regions, and was not always complete. Other brain regions
showed no evidence of recovery whatsoever."
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Ecstasy damages
the brain and impairs memory in humans
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A
NIDA-supported study has provided the first direct evidence that chronic use of
MDMA, popularly known as "ecstasy," causes brain damage in people. Using
advanced brain imaging techniques, the study found that MDMA harms neurons that
release serotonin, a brain chemical thought to play an important role in
regulating memory and other functions. In a related study, researchers found
that heavy MDMA users have memory problems that persist for at least 2 weeks
after they have stopped using the drug. Both studies suggest that the extent of
damage is directly correlated with the amount of MDMA use.
"The
message from these studies is that MDMA does change the brain and it looks like
there are functional consequences to these changes," says Dr. Joseph Frascella
of NIDA's Division of Treatment Research and Development. That message is
particularly significant for young people who participate in large, all-night
dance parties known as "raves," which are popular in many cities around the
Nation. NIDA's epidemiologic studies indicate that MDMA
(3,4-methylenedioxymethamphetamine) use has escalated in recent years among
college students and young adults who attend these social gatherings.
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These
brain scans show the amount of serotonin activity over a 40-minute period in a
non-MDMA user (top) and an MDMA user (bottom). Dark areas in the MDMA user's
brain show damage due to chronic MDMA use. |
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In the
brain imaging study, researchers used positron emission tomography (PET) to
take brain scans of 14 MDMA users who had not used any psychoactive drug,
including MDMA, for at least 3 weeks. Brain images also were taken of 15 people
who had never used MDMA. Both groups were similar in age and level of education
and had comparable numbers of men and women.
In
people who had used MDMA, the PET images showed significant reductions in the
number of serotonin transporters, the sites on neuron surfaces that reabsorb
serotonin from the space between cells after it has completed its work. The
lasting reduction of serotonin transporters occurred throughout the brain, and
people who had used MDMA more often lost more serotonin transporters than those
who had used the drug less.
Previous
PET studies with baboons also produced images indicating MDMA had induced
long-term reductions in the number of serotonin transporters. Examinations of
brain tissue from the animals provided further confirmation that the decrease
in serotonin transporters seen in the PET images corresponded to actual loss of
serotonin nerve endings containing transporters in the baboons' brains. "Based
on what we found with our animal studies, we maintain that the changes revealed
by PET imaging are probably related to damage of serotonin nerve endings in
humans who had used MDMA," says Dr. George Ricaurte of The Johns Hopkins
Medical Institutions in Baltimore. Dr. Ricaurte is the principal investigator
for both studies, which are part of a clinical research project that is
assessing the long-term effects of MDMA.
"The
real question in all imaging studies is what these changes mean when it comes
to functional consequences," says NIDA's Dr. Frascella. To help answer that
question, a team of researchers, which included scientists from Johns Hopkins
and the National Institute of Mental Health who had worked on the imaging
study, attempted to assess the effects of chronic MDMA use on memory. In this
study, researchers administered several standardized memory tests to 24 MDMA
users who had not used the drug for at least 2 weeks and 24 people who had
never used the drug. Both groups were matched for age, gender, education, and
vocabulary scores.
The
study found that, compared to the nonusers, heavy MDMA users had significant
impairments in visual and verbal memory. As had been found in the brain imaging
study, MDMA's harmful effects were dose-related: the more MDMA people used, the
greater difficulty they had in recalling what they had seen and heard during
testing.
The memory impairments found in MDMA users are among
the first functional consequences of MDMA-induced damage of serotonin neurons
to emerge. Recent studies conducted in the United Kingdom also have reported
memory problems in MDMA users assessed within a few days of their last drug
use. "Our study extends the MDMA-induced memory impairment to at least 2 weeks
since last drug use and thus shows that MDMA's effects on memory cannot be
attributed to withdrawal or residual drug effects," says Dr. Karen Bolla of
Johns Hopkins, who helped conduct the study.
The
Johns Hopkins/NIMH researchers also were able to link poorer memory performance
by MDMA users to loss of brain serotonin function by measuring the levels of a
serotonin metabolite in study participants' spinal fluid. These measurements
showed that MDMA users had lower levels of the metabolite than people who had
not used the drug; that the more MDMA they reported using, the lower the level
of the metabolite; and that the people with the lowest levels of the metabolite
had the poorest memory performance. Taken together, these findings support the
conclusion that MDMA-induced brain serotonin neurotoxicity may account for the
persistent memory impairment found in MDMA users, Dr. Bolla says.
Research on the functional consequences of
MDMA-induced damage of serotonin-producing neurons in humans is at an early
stage, and the scientists who conducted the studies cannot say definitively
that the harm to brain serotonin neurons shown in the imaging study accounts
for the memory impairments found among chronic users of the drug. However,
"that's the concern, and it's certainly the most obvious basis for the memory
problems that some MDMA users have developed," said Dr.
Ricaurte.
Findings from another Johns Hopkins/NIMH study now
suggest that MDMA use may lead to impairments in other cognitive functions
besides memory, such as the ability to reason verbally or sustain attention.
Researchers are continuing to examine the effects of chronic MDMA use on memory
and other functions in which serotonin has been implicated, such as mood,
impulse control, and sleep cycles. How long MDMA-induced brain damage persists
and the long-term consequences of that damage are other questions researchers
are trying to answer. Animal studies, which first documented the neurotoxic
effects of the drug, suggest that the loss of serotonin neurons in humans may
last for many years and possibly be permanent. "We now know that brain damage
is still present in monkeys 7 years after discontinuing the drug," Dr. Ricaurte
says. "We don't know just yet if we're dealing with such a long-lasting effect
in people." |
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