Ecstasy
users may encounter problems similar to those experienced by amphetamine and
cocaine users, including addiction. In addition to its rewarding effects,
ecstasy's psychological effects can include confusion, depression, sleep problems,
anxiety, and paranoia. These effects can sometimes last 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. Ecstasy-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. Ecstasy
use damages brain serotonin neurons. Serotonin is thought to play a role in
regulating mood, memory, sleep, and appetite. Recent research indicates heavy
ecstasy use causes persistent memory problems in humans.
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 for 6 to 7 years. 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 amphetamines. 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."
Ecstasy
damages the brain and impairs memory in humans
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.
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 were also taken of
15 people who had never used MDMA. Both groups were similar in age and level
of education. The study used 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
re-absorb 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 have also 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 were also 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. 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."