Archive for the ‘ Substance Abuse ’ Category

Marijuana users substitute alcohol at age 21

A recent study looked at marijuana and alcohol use in people between the ages of 18 and 24. It’s probably not surprising that the results show a drastic increase in alcohol consumption in people just over 21; after all, that’s the minimum legal age to drink. What University of Illinois economist Ben Crost found remarkable is that, at the same age, there was an equally dramatic drop in marijuana use.

“Alcohol appears to be a substitute for marijuana. This sudden decrease in the use of marijuana is because they suddenly have easy access to alcohol,” Crost said.

Crost and Santiago Guerrero used five years of data from the National Survey on Drug Use and Health. Survey participants estimated how many days in the past 30 that they had alcoholic drinks or used marijuana. Because the precise age of each respondent was not known, data on the averages of substance use by month of age was obtained from the U.S. Department of Health and Human Services’ Substance Abuse and Mental Health Services Administration.

The minimum legal drinking age provided a threshold for comparison.

Legal Drinking Age Changes

“Whenever there is a discontinuous threshold where something changes, it provides a way to identify a causal effect,” Crost said. “You can compare people right above and right below the threshold. They should be very similar in all other respects, except for that one difference.

“In this case, we looked at the cutoff that occurs when people, overnight get much easier access to alcohol. People who are 20 years and 11 months old are basically the same as people who are 21 with that one exception. Nothing should change about people’s preference because people don’t overnight lose their preference for marijuana. They use it or lose it over the long run but not from one month to the next.”

Crost said that all of the costs and benefits from policies designed to reduce alcohol consumption, such as the minimum legal drinking age or liquor taxes, need to be assessed.

“We need to take this possible substitution behavior into account,” Crost said. “Marginally lowering the minimum legal drinking age would decrease the probability of marijuana consumption in young adults by about 10 percent. So, policies aimed at restricting alcohol consumption among young adults are likely to have the unintended consequence of increasing the use of illegal drugs, such as marijuana.

Alcohol Availability Decreases Marijuana Use

“If you think alcohol is much more harmful to people’s health, then you should probably restrict alcohol use. If you think marijuana is more harmful, then you might want to consider loosening the restrictions for alcohol,” he said.

The study also analyzed men and women separately. Although men have higher baseline use levels of both alcohol and marijuana, the effect of the minimum legal drinking age is larger for women. For example, the frequency of marijuana use for men decreased 7.5 percent. Women’s frequency of use decreased 15 percent.

“The effect of alcohol availability on marijuana use: Evidence from the minimum legal drinking age” by Benjamin Crost and Santiago Guerrero was published in the Journal of Health Economics.

July 12th, 2015  in Substance Abuse No Comments »

Medication Could Help With Addiction

Researchers at The University of Texas at Austin have successfully stopped cocaine and alcohol addiction in experiments using a drug already approved by the U.S. Food and Drug Administration (FDA) to treat high blood pressure. If the treatment is proven effective in humans, it would be the first of its kind — one that could help prevent relapses by erasing the unconscious memories that underlie addiction.

The research is published this week in the journal Molecular Psychiatry.

Scientists once believed that drug addiction was simply a physical craving: Drug addicts who became sober and then later relapsed merely lacked willpower. But that view has gradually shifted since the 1970s.

Today, most experts acknowledge that environmental cues — the people, places, sights and sounds an addict experiences leading up to drug use — are among the primary triggers of relapses. It was an environmental cue (a ringing bell) that caused the dogs in Ivan Pavlov’s famous experiments to salivate, even when they couldn’t see or smell food.

Caused Rats to ‘Forget’ Addiction

Led by Hitoshi Morikawa, associate professor of neuroscience at The University of Texas at Austin, a team of researchers trained rats to associate either a black or white room with the use of a drug. Subsequently, when the addicted rats were offered the choice of going into either room, they nearly always chose the room they associated with their addiction.

Then one day, the researchers gave the addicted rats a high dose of an antihypertensive drug called isradipine before the rats made their choices. Although rats still preferred the room they associated with their addiction on that day, they no longer showed a preference for it on subsequent days. In fact, the lack of preference persisted in the isradipine-treated group in ways that couldn’t be found in a control group — suggesting the addiction memories were not just suppressed but had gone away entirely.

“The isradipine erased memories that led them to associate a certain room with cocaine or alcohol,” said Morikawa.

Addictive drugs are thought to rewire brain circuits involved in reward learning, forming powerful memories of drug-related cues. Antihypertensive drugs all block a particular type of ion channel, which is expressed not only in heart and blood vessels but also in certain brain cells. The researchers found that blocking these ion channels in brain cells, using isradipine, appears to reverse the rewiring that underlies memories of addiction-associated places.

Might Help Addicts Become De-Addicted

There are already medications that have been shown to prevent people from feeling euphoria when they take an addictive drug and that might prevent them from developing an addiction. A treatment based on this latest research, however, would be much more effective, said Morikawa, targeting the associations an addict has with the experience leading up to taking a drug.

“Addicts show up to the rehab center already addicted,” he said. “Many addicts want to quit, but their brains are already conditioned. This drug might help the addicted brain become de-addicted.”

Morikawa noted that because isradipine is already labeled as safe for human use by the FDA, clinical trials could potentially be carried out much more quickly than with nonapproved drugs.

One challenge with using isradipine in high doses to treat addiction is that it lowers blood pressure. So it might be necessary to pair it with other treatments that prevent blood pressure from falling too low.

June 28th, 2015  in Substance Abuse No Comments »

I Had to Hit Bottom With Meth

By James S.
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By James S.

What It Was Like

I took my first drink at age 12 and soon after started to use drugs. I used and drank for many years without major consequences. At the age of 20 I got a DUI and was arrested 12 times for alcohol-related offenses so I used drugs to change the way that I was feeling. In my mid-30s I started to use meth and loved it. All my morals were going down hill and I really did not realize it. I had two kids out of wedlock and was with a number of girls.

What Happened?

In 2007, I was using everyday and I was loosing every thing that I had worked for. In October, I was dealing drugs to support my habit. I took some meth to a motel room that my kids mother was staying at and sold it to her friend that was selling small amounts.

My kids were also staying there at that time. The next morning when they woke up the guy kicked my kid’s mother out of that room because he said she stole dope from him.

She took my two daughters to me and all that afternoon my two girls were sick throwing up and I thought that they just had a stomach bug.

A few weeks later Children Youth Families Dept. (CYFD) was wanting to talk to me and kid’s mother. The guy that had blamed her for steeling his dope turned us in and said we were using around our kids. He also made a lot of other accusations that were not true just to get her in trouble.

They tested all of us and we all were dirty, even our kids. My kids were ages 2 and 3 years old and they tested at higher levels of meth than we did. I couldn’t understand it because I thought that I kept it away from my kids. I would smoke it in another room.

CYFD and the police came and took my kids into custody. That was the day that I believe that I hit bottom. I did not know what to do, so I just kept getting high and drunk. I was going insane fast. I really started to go crazy and I didn’t see any way out. I didn’t think life was worth living any longer.

You see I thought that when CYFD took kids it was almost impossible to get them back.

I came up with a plan, I was going to shoot the guy that turned us in and then I was going to turn the gun on myself and end the pain. That is when a friend talked me into going to the hospital and turning myself in because I was a danger to myself and others. He also took my gun.

I was in there for a few days then went to rehab for 28 days. I got out of rehab and started to go to NA and AA. I was there every time the doors were open. I got a sponsor and took the steps and got involved in service work in the program. The judge gave me my kids back and now I stay sober and clean for me.

Lessons Learned

  • My life has changed so much today I am a productive member of society. I wear a badge today and get to help people everyday in a good way. I do a lot of work with the same judge that told me that if I did not change the way that I was living then I would never have my kids with me.
  • I thank God for all the people who have helped me. I will never be able to pay back what has been given to me so I just try to live right and help other people everyday.
  • I found out that 12 step programs work when I am willing to work the program.
  • Today I have a little over 4 years in recovery. I’m glad I made it into recovery.

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June 25th, 2015  in Illegal Drugs No Comments »

Marijuana users who feel low get high

Adolescents and young adults who smoke marijuana frequently may attempt to manage negative moods by using the drug, according to a study in September’s Journal of Studies on Alcohol and Drugs.

“Young people who use marijuana frequently experience an increase in negative affect in the 24 hours leading up to a use event, which lends strong support to an affect-regulation model in this population,” says the study’s lead author Lydia A. Shrier, M.D., M.P.H., of the division of adolescent and young adult medicine at Boston Children’s Hospital.

Feeling Good Is Temporary

She notes that using marijuana as a coping technique for negative affect may make it harder for people to stop using the drug.

“One of the challenges is that people often may use marijuana to feel better but may feel worse afterward,” she says. “Marijuana use can be associated with anxiety and other negative states. People feel bad, they use, and they might momentarily feel better, but then they feel worse. They don’t necessarily link feeling bad after using with the use itself, so it can become a vicious circle.”

Negative Effects Increased

For the study, Shrier and colleagues recruited 40 people, ages 15 to 24, who used marijuana at least twice a week, although their average was 9.7 times per week. They were trained to use a handheld computer that signaled them at a random time within three-hour intervals (four to six times per day) for two weeks. At each signal, participants were asked about their mood, companionship, perceived availability of marijuana, and recent marijuana use. Participants were also asked to report just before and just after any marijuana use. They completed more than 3,600 reports.

The researchers found that negative affect was significantly increased during the 24 hours before marijuana use compared with other periods. However, positive affect did not vary in the period before marijuana use compared with other times.

Also, neither the availability of marijuana nor the presence of friends modified the likelihood that chronic users would use marijuana following a period of negative affect.

Real-Time Mood Assessment

The study is unique in that it collected data in real time to assess mood and marijuana use events. The study thus was able to identify mood that was occurring in the 24 hours before marijuana use and compared it with mood at other times, Shrier reports.

“There are a host of limitations with retrospective assessments, such as asking people ‘the last time you used marijuana, why did you use it?'” according to Shrier. “We weren’t asking people to predict anything or to recall anything—we were just asking them to give us reports about how they were feeling right now. We were able to put under a microscope the association between those feelings and subsequent marijuana use.”

Shrier says it could be beneficial for clinicians and counselors to help their patients identify patterns of negative affect and to implement alternative mood-regulation strategies to replace marijuana use.

September 18th, 2014  in Substance Abuse No Comments »

Federal Club Drug Law: More Harm Than Good?

A federal law enacted to combat the use of “club drugs” such as Ecstasy — and today’s variation known as Molly — has failed to reduce the drugs’ popularity and, instead, has further endangered users by hampering the use of measures to protect them.

University of Delaware sociology professor Tammy L. Anderson makes that case in a paper she will present at the 109th Annual Meeting of the American Sociological Association. The paper, which has been accepted for publication this fall in the American Sociological Association journal Contexts, examines the unintended consequences of the 2003 RAVE (Reducing Americans’ Vulnerability to Ecstasy) Act.

Holding Rave Promoters Accountible

The act was designed to address the use of drugs, sometimes by very young teens, at the all-night electronic-dance-music parties known as raves that were especially common in the 1990s.

The law targeted club owners and promoters, holding them criminally responsible for illegal drug use at their events.

And that’s the problem, Anderson says. Before the law was passed, raves often provided services to help protect participants who were using drugs: free bottled water was available to combat the dehydration that can occur, for example, and security staff patrolled the event on the lookout for anyone in distress who might need medical care. Independent groups, such as Dance Safe, sometimes set up booths outside raves and tested the drugs people were carrying to alert them to dangerous ingredients.

“There were a lot of groups like that, and there was a lot of educational information about drugs being made available,” Anderson says. “Today, clubs and promoters are reluctant to take those precautions because it could be used as evidence against them.” They sometimes even fail to summon medical help when needed, she says.

Ineffective in Curtailing Drug Use

At the same time, the RAVE Act has clearly been ineffective in curtailing drug use at club events, Anderson says. Participants now widely use the drug Molly — for MDMA, the ingredient in Ecstasy — to stay awake for what is often a 24-hour party. Deaths from the use of Molly are not uncommon, according to Anderson, who cites examples such as the two 20-somethings who died at the 2013 Electronic Zoo (EZoo) festival in New York.

“The RAVE Act is a relic of the War on Drugs,” she says. “It never worked in the past, and it’s not working now.”

Anderson has conducted extensive research on raves, drug use, and the youth culture, including five years of intensive observations and interviews of rave participants on the East Coast of the U.S. and in London and Spain, supported by a grant from the National Institute of Justice. She is the author of Rave Culture: The Alteration and Decline of a Music Scene (Temple University Press, 2009).

August 23rd, 2014  in Illegal Drugs No Comments »

Students dismiss drugged driving dangers

Underage male college students who report using marijuana in the month before they were surveyed had a high prevalence of driving under its influence and of riding with a marijuana-using driver, at a rate more than double that of driving or riding after alcohol use, say researchers from the University of Massachusetts Amherst School of Public Health and Health Sciences and University of Washington pediatrics department.

Frequently Drive After Smoking

Among other things, this study found that among marijuana-using students, 44 percent of males and 9 percent of females drove after using the drug, and 51 percent of males and 35 percent of females rode as a passenger with a marijuana-using driver.

Lead author Jennifer Whitehill at UMass Amherst and colleagues say their findings probably reflect the widespread myth that driving after marijuana use is safe. The researchers suggest that developing strategies to combat this belief could help to change social norms and encourage using a designated driver not only after alcohol use, but after a driver has used any risky substance. Study findings are in the current issue of the JAMA Pediatrics.

Marijuana Is Not Totally Safe

Whitehill says, “There seems to be a misconception that marijuana use is totally safe, but as an injury prevention researcher I dispute that. We’ve done a good job in public health with messages about the risks of driving after alcohol use. Clearly the idea not to drink and drive has come through for these students, because we found only 7 percent engage in that behavior. But our study suggests we must do better when it comes to marijuana, since we found that 31 percent of marijuana-using students drive under its influence.”

The health policy professor adds, “What I feel is, let’s create a culture where we don’t engage in any of these risk enhancing behaviors before we get behind the wheel.”

With the decriminalization of marijuana in 16 states and its availability increasing with medical use, concerns about drug-impaired drivers are more and more relevant, the authors point out. “The issue of marijuana-impaired driving is particularly salient for young drivers, for whom the combination of inexperience and substance use elevates crash risk. If they are part of a culture that accepts the behavior, their risks increase at a predictable rate that we understand better now,” Whitehill says.

Smoking, Drinking and Driving

The results describe the prevalence, sex differences and risk factors associated with underage college students’ driving after marijuana use, after using alcohol and riding with a driver using either substance.

Data for this report came from an ongoing longitudinal study. The researchers approached 640 incoming freshmen 18 years old at the University of Washington and University of Wisconsin, Madison, of who 338 agreed to take part. Overall, 30 percent of male and 13 percent of female study participants said they used marijuana in the 28 days prior to being surveyed, while 67 percent of the men and 64 of the women reported using alcohol over the same period. Overall, 23 percent of the men reported using both marijuana and alcohol over the previous month compared to just 9 percent of the women.

Whitehill notes, “Our findings are consistent with common knowledge and anecdotes indicating that students drive after using marijuana. And it wasn’t surprising to find that more men in particular drive after using marijuana compared to women. But our study quantifies the prevalence, which is useful in setting priorities for public health action. We also quantified the likelihood that someone will ride as a passenger with a driver who has used marijuana, and how much it rises with the proportion of their friends who use marijuana.”

Increased Risk of Crashes

Despite its limitations, including the small number of nonwhite participants and reliance on self-reported drug use, the study’s findings represent “an important and timely contribution” to knowledge about older adolescents’ driving after drug use, the authors say. Findings “supplement our knowledge that marijuana use increases the risk of motor vehicle crashes by estimating how common it is for underage students to have taken this risk with the past 28 days.”

May 20th, 2014  in Substance Abuse No Comments »

Marijuana involved in more Colorado accidents

The proportion of marijuana-positive drivers involved in fatal motor vehicle crashes in Colorado has increased dramatically since the commercialization of medical marijuana in the middle of 2009, according to a study by University of Colorado School of Medicine researchers.

With data from the National Highway Traffic Safety Administration’s Fatality Analysis Reporting System covering 1994 to 2011, the researchers analyzed fatal motor vehicle crashes in Colorado and in the 34 states that did not have medical marijuana laws, comparing changes over time in the proportion of drivers who were marijuana-positive and alcohol-impaired.

Drivers Testing Positive

The researchers found that fatal motor vehicle crashes in Colorado involving at least one driver who tested positive for marijuana accounted for 4.5 percent in the first six months of 1994; this percentage increased to 10 percent in the last six months of 2011.

They reported that Colorado underwent a significant increase in the proportion of drivers in a fatal motor vehicle crash who were marijuana-positive after the commercialization of medical marijuana in the middle of 2009. The increase in Colorado was significantly greater compared to the 34 non-medical marijuana states from mid-2009 to 2011.

The researchers also reported no significant changes over time in the proportion of drivers in a fatal motor vehicle crash who were alcohol-impaired within Colorado and comparing Colorado to the 34 non-medical marijuana states.

Stacy Salomonsen-Sautel, Ph.D, who was a postdoctoral fellow in the Department of Pharmacology, is the lead author of the study, which is available online in the journal Drug and Alcohol Dependence. Christian Hopfer, MD, associate professor of psychiatry, is the senior author.

Serious Concerns

Salomonsen-Sautel said the study raises important concerns about the increase in the proportion of drivers in a fatal motor vehicle crash who were marijuana-positive since the commercialization of medical marijuana in Colorado, particularly in comparison to the 34 non-medical marijuana states.

While the study does not determine cause and effect relationships, such as whether marijuana-positive drivers caused or contributed to the fatal crashes, it indicates a need for better education and prevention programs to curb impaired driving.

May 20th, 2014  in Substance Abuse No Comments »

Why Some Pot Smokers Are Slackers

Researchers found that dopamine levels in a part of the brain called the striatum were lower in people who smoke more cannabis and those who began taking the drug at a younger age.
They suggest this finding could explain why some cannabis users appear to lack motivation to work or pursue their normal interests.
The study, by scientists at Imperial College London, UCL and King’s College London, was funded by the Medical Research Council and published in the journal Biological Psychiatry.
The researchers used PET brain imaging to look at dopamine production in the striatum of 19 regular cannabis users and 19 non-users of matching age and sex.
The cannabis users in the study had all experienced psychotic-like symptoms while smoking the drug, such as experiencing strange sensations or having bizarre thoughts like feeling as though they are being threatened by an unknown force.
The researchers expected that dopamine production might be higher in this group, since increased dopamine production has been linked with psychosis. Instead, they found the opposite effect.
The cannabis users in the study had their first experience with the drug between the ages of 12 and 18. There was a trend for lower dopamine levels in those who started earlier, and also in those who smoke more cannabis. The researchers say these findings suggest that cannabis use may be the cause of the difference in dopamine levels.
The lowest dopamine levels were seen in users who meet diagnostic criteria for cannabis abuse or dependence, raising the possibility that this measure could provide a marker of addiction severity.
Previous research has shown that cannabis users have a higher risk of mental illnesses that involve repeated episodes of psychosis, such as schizophrenia.
“It has been assumed that cannabis increases the risk of schizophrenia by inducing the same effects on the dopamine system that we see in schizophrenia, but this hasn’t been studied in active cannabis users until now,” said Dr Michael Bloomfield, from the Institute of Clinical Sciences at Imperial, who led the study.
“The results weren’t what we expected, but they tie in with previous research on addiction, which has found that substance abusers – people who are dependent on cocaine or amphetamine, for example – have altered dopamine systems.
“Although we only looked at cannabis users who have had psychotic-like experiences while using the drug, we think the findings would apply to cannabis users in general, since we didn’t see a stronger effect in the subjects who have more psychotic-like symptoms. This needs to be tested though.
“It could also explain the ‘amotivational syndrome’ which has been described in cannabis users, but whether such a syndrome exists is controversial.”
Other studies have looked at dopamine release in former cannabis users and not seen differences with people who haven’t taken cannabis, suggesting that the effects seen in this study are likely to be reversible.

Researchers found that dopamine levels in a part of the brain called the striatum were lower in people who smoke more cannabis and those who began taking the drug at a younger age.

They suggest this finding could explain why some cannabis users appear to lack motivation to work or pursue their normal interests.

The study, by scientists at Imperial College London, UCL and King’s College London, was funded by the Medical Research Council and published in the journal Biological Psychiatry.

Lack of Dopamine Production

The researchers used PET brain imaging to look at dopamine production in the striatum of 19 regular cannabis users and 19 non-users of matching age and sex.

The cannabis users in the study had all experienced psychotic-like symptoms while smoking the drug, such as experiencing strange sensations or having bizarre thoughts like feeling as though they are being threatened by an unknown force.

The researchers expected that dopamine production might be higher in this group, since increased dopamine production has been linked with psychosis. Instead, they found the opposite effect.

Smokers Started Early

The cannabis users in the study had their first experience with the drug between the ages of 12 and 18. There was a trend for lower dopamine levels in those who started earlier, and also in those who smoke more cannabis. The researchers say these findings suggest that cannabis use may be the cause of the difference in dopamine levels.

The lowest dopamine levels were seen in users who meet diagnostic criteria for cannabis abuse or dependence, raising the possibility that this measure could provide a marker of addiction severity.

Previous research has shown that cannabis users have a higher risk of mental illnesses that involve repeated episodes of psychosis, such as schizophrenia.

Results Not Expected

“It has been assumed that cannabis increases the risk of schizophrenia by inducing the same effects on the dopamine system that we see in schizophrenia, but this hasn’t been studied in active cannabis users until now,” said Dr Michael Bloomfield, from the Institute of Clinical Sciences at Imperial, who led the study.

“The results weren’t what we expected, but they tie in with previous research on addiction, which has found that substance abusers – people who are dependent on cocaine or amphetamine, for example – have altered dopamine systems.

“Although we only looked at cannabis users who have had psychotic-like experiences while using the drug, we think the findings would apply to cannabis users in general, since we didn’t see a stronger effect in the subjects who have more psychotic-like symptoms. This needs to be tested though.

Amotivational Syndrome

“It could also explain the ‘amotivational syndrome’ which has been described in cannabis users, but whether such a syndrome exists is controversial.”

Other studies have looked at dopamine release in former cannabis users and not seen differences with people who haven’t taken cannabis, suggesting that the effects seen in this study are likely to be reversible.

July 4th, 2013  in Illegal Drugs 1 Comment »

Cocaine vaccine passes key testing hurdle

Researchers at Weill Cornell Medical College have successfully tested their novel anti-cocaine vaccine in primates, bringing them closer to launching human clinical trials.

Their study, published online by the journal Neuropsychopharmacology, used a radiological technique to demonstrate that the anti-cocaine vaccine prevented the drug from reaching the brain and producing a dopamine-induced high.

“The vaccine eats up the cocaine in the blood like a little Pac-man before it can reach the brain,” says the study’s lead investigator, Dr. Ronald G. Crystal, chairman of the Department of Genetic Medicine at Weill Cornell Medical College.

Breaking the Addiction

“We believe this strategy is a win-win for those individuals, among the estimated 1.4 million cocaine users in the United States, who are committed to breaking their addiction to the drug,” he says. “Even if a person who receives the anti-cocaine vaccine falls off the wagon, cocaine will have no effect.”

Dr. Crystal says he expects to begin human testing of the anti-cocaine vaccine within a year.

Cocaine, a tiny molecule drug, works to produce feelings of pleasure because it blocks the recycling of dopamine — the so-called “pleasure” neurotransmitter — in two areas of the brain, the putamen in the forebrain and the caudate nucleus in the brain’s center. When dopamine accumulates at the nerve endings, “you get this massive flooding of dopamine and that is the feel good part of the cocaine high,” says Dr. Crystal.

Immune System Fights Cocaine

The novel vaccine Dr. Crystal and his colleagues developed combines bits of the common cold virus with a particle that mimics the structure of cocaine. When the vaccine is injected into an animal, its body “sees” the cold virus and mounts an immune response against both the virus and the cocaine impersonator that is hooked to it. “The immune system learns to see cocaine as an intruder,” says Dr. Crystal. “Once immune cells are educated to regard cocaine as the enemy, it produces antibodies, from that moment on, against cocaine the moment the drug enters the body.”

In their first study in animals, the researchers injected billions of their viral concoction into laboratory mice, and found a strong immune response was generated against the vaccine. Also, when the scientists extracted the antibodies produced by the mice and put them in test tubes, it gobbled up cocaine. They also saw that mice that received both the vaccine and cocaine were much less hyperactive than untreated mice given cocaine.

Booster Shots to Dampen the Cocaine High

In this study, the researchers sought to precisely define how effective the anti-cocaine vaccine is in non-human primates, who are closer in biology to humans than mice.

They developed a tool to measure how much cocaine attached to the dopamine transporter, which picks up dopamine in the synapse between neurons and brings it out to be recycled. If cocaine is in the brain, it binds on to the transporter, effectively blocking the transporter from ferrying dopamine out of the synapse, keeping the neurotransmitter active to produce a drug high.

In the study, the researchers attached a short-lived isotope tracer to the dopamine transporter. The activity of the tracer could be seen using positron emission tomography (PET). The tool measured how much of the tracer attached to the dopamine receptor in the presence or absence of cocaine.

Reducing Cocaine Occupancy

The PET studies showed no difference in the binding of the tracer to the dopamine transporter in vaccinated compared to unvaccinated animals if these two groups were not given cocaine. But when cocaine was given to the primates, there was a significant drop in activity of the tracer in non-vaccinated animals. That meant that without the vaccine, cocaine displaced the tracer in binding to the dopamine receptor.

Previous research had shown in humans that at least 47 percent of the dopamine transporter had to be occupied by cocaine in order to produce a drug high. The researchers found, in vaccinated primates, that cocaine occupancy of the dopamine receptor was reduced to levels of less than 20 percent.

“This is a direct demonstration in a large animal, using nuclear medicine technology, that we can reduce the amount of cocaine that reaches the brain sufficiently so that it is below the threshold by which you get the high,” says Dr. Crystal.

Frequency of Vaccine?

When the vaccine is studied in humans, the non-toxic dopamine transporter tracer can be used to help study its effectiveness as well, he adds.

The researchers do not know how often the vaccine needs to be administered in humans to maintain its anti-cocaine effect. One vaccine lasted 13 weeks in mice and seven weeks in non-human primates.

“An anti-cocaine vaccination will require booster shots in humans, but we don’t know yet how often these booster shots will be needed,” says Dr. Crystal. “I believe that for those people who desperately want to break their addiction, a series of vaccinations will help.”

May 11th, 2013  in Illegal Drugs No Comments »

Breath study brings roadside drug testing closer

A group of researchers from Sweden have provided further evidence that illegal drugs can be detected in the breath, opening up the possibility of a roadside breathalyzer test to detect substances such as cocaine, amphetamines and cannabis.

Using a simple, commercially available breath sampler, the researchers have successfully identified a range of 12 substances in the breath of 40 patients recruited from a drug emergency clinic in Stockholm.

Their findings have been published in IOP Publishing’s Journal of Breath Research.

Advantages of Breath Tests

Blood, urine and saliva are the most popular methods for detecting illegal drugs and are already used by law enforcement in a number of countries; however, exhaled breath is seen as a promising alternative as it’s easier to collect, non-invasive, less prone to adulteration and advantageous when location becomes an obstacle, such as at the roadside.

Exhaled breath contains very small particles that carry non-volatile substances from the airway lining fluid. Any compound that has been inhaled, or is present in the blood, may contaminate this fluid and pass into the breath when the airways open. The compounds will then be exhaled and can subsequently be detected.

In this study, researchers from the Karolinska Institute in Stockholm collected breath, blood plasma and urine samples from 47 patients (38 males, 9 females) who had taken drugs in the previous 24 hours and were recovering at a drug addiction emergency clinic.

Analyzing the Samples

Interviews were also undertaken with each patient to assess their history of drug use.

The breath samples were taken using a commercially available sampling device – SensAbues – and then analysed using liquid chromatography and mass spectrometry.

The portable sampling device consists of a mouth piece and a micro-particle filter. When a patient breathes into the mouth piece, saliva and larger particles are separated from the micro-particles that need to be measured.

The micro-particles are able to pass through and deposit onto a filter, which can then be sealed and stored ready for analysis. Breath samples were analysed for twelve substances.

Alprazolam and benzoylecgonine were detected in exhaled breath for the first time, whereas for methadone, amphetamine, methamphetamine, cocaine, morphine, 6-acetylmorphine, tetrahydrocannabinol, buprenorphine, diazepam and oxazepam, the results confirmed previous observations.

Detected 24 Hours Later

“Considering the samples were taken 24 hours after the intake of drugs, we were surprised to find that there was still high detectability for most drugs,” said lead author of the study Professor Olof Beck.

“In cases of suspected driving under the influence of drugs, blood samples could be taken in parallel with breath when back at a police station. Future studies should therefore test the correlation between blood concentration of drugs of abuse and the concentrations in exhaled breath.”

May 1st, 2013  in Substance Abuse No Comments »