
Ecstasy
Side Effects 
MDMA or ecstasy is a Schedule
I synthetic, psychoactive drug possessing stimulant and hallucinogenic properties.
Ecstasy possesses chemical variations of the stimulant amphetamine or methamphetamine
and a hallucinogen, most often mescaline. Commonly referred to as Ecstasy or
XTC, MDMA was first synthesized in 1912 by a German company possibly to be used
as an appetite suppressant. Chemically, it is an analogue of MDA, a drug that
was popular in the 1960s. Today Ecstasy is most often distributed at late-night
parties called "raves", nightclubs, and rock concerts. As the rave
and club scene expands to metropolitan and suburban areas across the country,
ecstasy use and distribution are increasing as well.
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 ecstasy
scored lower on memory tests.
"The serotonin
system, which is compromised by ecstasy, 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 ecstasy, 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 ecstasy are those that use the
chemical serotonin to communicate with other neurons. The Hopkins team
had also previously conducted brain imaging research in human ecstasy
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."
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.
These brain scans show the amount of serotonin activity over a 40-minute
period in a non-MDMA user (left) and an MDMA user (right). Dark areas in
the MDMA user's brain show damage due to chronic MDMA use.
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," Dr. Ricaurte says.
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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