Substance Abuse News

A study published in the scientific journal Addiction shows that the Mexican government’s recent efforts to control the manufacture of methamphetamine have caused a drop in methamphetamine treatment admissions in Mexico and in neighbouring Texas.

In 2005 Mexico began controlling its imports of pseudoephedrine (a precursor chemical used in the manufacture of methamphetamine), and in 2008 it became the first country in North America to ban all imports of pseudoephedrine as well as ephedrine, another important precursor chemical. Researchers estimate that the 2005 import controls caused a 12% drop in voluntary methamphetamine treatment admissions in Mexico, with similar reductions in Texas.

An even larger drop in voluntary admissions occurred following the 2007 closure of a commercial chemical company suspected of illicitly importing more than 60 tons of pseudoephedrine into Mexico. The head of the company fled Mexico but was eventually arrested in the United States. Methamphetamine treatment admissions in Mexico decreased by 56% following the closure of the company, with Texas showing similar results.

Signs of Meth Decline

All decreases in admissions appeared to be specific to methamphetamine, as researchers found no concurrent changes in cocaine, heroin, and alcohol treatment admissions during the same period. The study wound up shortly after the 2008 bans on precursor chemicals came into effect, so researchers weren’t able to examine fully the impact of those bans; however, the researchers noted that treatment admissions in Mexico showed signs of declining in the first few months following the bans.

Says lead researcher James Cunningham, a Fulbright Scholar at The University of Arizona: “These findings constitute the first evidence outside the United States that a country’s precursor chemical controls can have positive public health results both domestically and internationally.”

Standard therapeutic techniques decrease cravings of cigarette smokers by regulating activity in two separate but related areas of the brain, a new study led by a Yale University researcher shows.

Smokers who are taught cognitive strategies, such as thinking about the long-term consequences of smoking, show increased activity in the prefrontal cortex, an area of the brain associated with cognitive control and rational thought. They also show decreased activity in areas of the striatum, an area of the brain associated with drug craving and reward-seeking behavior, according to the paper published online Aug. 2 in the Proceedings of the National Academy of Sciences.

“This shows that smokers can indeed control their cravings, they just need to be told how to do it,” said Hedy Kober, assistant professor of psychiatry at the Yale School of Medicine and lead author of the paper.

Cravings Trigger Relapse

Cravings are the triggers that often lead to relapse in a host of addictions, which carry a staggering economic and social cost. Cigarette smoking alone is responsible for over 400,000 deaths per year in the U.S. (more than all illicit drugs and alcohol combined). Some experts predict that substance abusers should show impairments in areas of the prefrontal cortex, which among other functions helps control emotion. But in smokers at least, this does not appear to be the case. This area of the brain showed increased activity—and smokers reported less intense cravings—when using cognitive strategies.

Cognitive behavioral therapy has been shown to be an effective tool in treating a variety of mental health disorders, including substance use disorders. The new study shows why this approach is effective, Kober said.

“We do not see any impairment in the prefrontal cortex, which suggests the brain is able, when prompted, to recruit control regions to reduce cravings,” Kober said.

Child abuse is a serious problem that affects nearly one million children a year in the United States alone. The American Academy of Pediatrics and the US Department of Health and Human Services classify child abuse into four categories including neglect, physical abuse, sexual abuse, and emotional abuse. None of these categories, however, clearly includes the abusive use of drugs on children. A study soon to be published in the Journal of Pediatrics investigates the malicious use of pharmaceuticals and attempts to shed light on this under-recognized problem.

Dr. Shan Yin from the University of Colorado and the Rocky Mountain Poison Drug Center at Denver Health reviewed cases of pharmaceutical abuse reported to the National Poison Data System between 2000 and 2008. Dr. Yin included reports of the malicious use of alcohol, painkillers, cough and cold medicines, sedatives and sleeping pills, and antipsychotic medicines.

Using Drugs to Subdue Children

Of the more than 1400 cases studied, nearly 14% resulted in moderate to major consequences, including death. Nearly one-half of the abused children were exposed to at least one sedative. An average of 160 cases, including two deaths, was reported each year. Motives and legal findings were unavailable for these particular cases; however, motives for the abusive use of drugs generally are varied, and can include punishment, amusement, or a wish for a break from childcare responsibilities.

This study illustrates the seriousness of the abusive use of drugs administered to children. According to Dr. Yin, “The malicious administration of pharmaceuticals should be considered an important form of child abuse.” He encourages pediatricians and emergency medical personnel to be on the watch for this form of maltreatment, and suggests the use of comprehensive drug screening during the evaluation of a child suspected to be the victim of abuse. Dr. Yin also cautions parents that the “non-therapeutic administration of pharmaceuticals to children can result in serious outcomes, including death.”

Why is it that only some drug users become addicts? This is the question that has been addressed by the teams of Pier Vincenzo Piazza and Olivier Manzoni, at the Neurocentre Magendie in Bordeaux (Inserm unit 862). These researchers have just discovered that the transition to addiction could result from a persistent impairment of synaptic plasticity in a key structure of the brain. This is the first demonstration that a correlation exists between synaptic plasticity and the transition to addiction. The results from the teams at Neurocentre Magendie call into question the hitherto held idea that addiction results from pathological cerebral modifications which develop gradually with drug usage. Their results show that addiction may, instead, come from a form of anaplasticity, i.e. from incapacity of addicted individuals to counteract the pathological modifications caused by the drug to all users.

This research is published in the journal Science on 25 June 2010.

Developing Drug Addiction

The voluntary consumption of drugs is a behaviour found in many species of animal. However, it had long been considered that addiction, defined as compulsive and pathological drug consumption, is a behaviour specific to the human species and its social structure. In 2004, the team of Pier Vincenzo Piazza showed that the behaviours which define addiction in humans, also appear in some rats which will self administer cocaine. Addiction exhibits astonishing similarities in men and rodents, in particular the fact that only a small number of consumers (humans or rodents) develop a drug addiction. The study of drug dependent behaviour in this mammal model thus opened the way to the study of the biology of addiction.

Today, thanks to a fruitful collaboration, the teams of Pier Vincenzo Piazza and Olivier Manzoni are reporting discovery of the first known biological mechanisms for the transition from regular but controlled drug taking to a genuine addiction to cocaine, characterised by a loss of control over drug consumption.

Chronic exposure to drugs causes many modifications to the physiology of the brain. Which of these modifications is responsible for the development of an addiction? This is the question the researchers wanted to answer in order to target possible therapeutic approaches to a disorder for which treatments are cruelly lacking.

Some Become Addicted, Some Don’t

The addiction model developed in Bordeaux provides a unique tool to answer this question. Thus it allows comparing animals who took identical quantities of drugs, but of which only few become addicted. By comparing addict and non-addict animals at various time points during their history of drug taking, the teams of Pier Vincenzo Piazza and Olivier Manzoni have demonstrated that the animals which developed an addiction to cocaine exhibit a permanent loss of the capacity to produce a form of plasticity known as long term depression (or LTD). LTD refers to the ability of the synapses (the region of communication between neurons) to reduce their activity under the effect of certain stimulations. It plays a major role in the ability to develop new memory traces and, consequently, to demonstrate flexible behaviour.

After short term usage of cocaine, LTD is not modified. However, after a longer use, a significant LTD deficit appears in all users. Without this form of plasticity, which allows new learning to occur, behaviour with regard to the drug becomes more and more rigid, opening the door to development of a compulsive consumption. The brain of the majority of users is able to produce the biological adaptations which allow to counteract the effects of the drug and to recover a normal LTD. By contrast, the anaplasticity (or lack of plasticity) exhibited by the addicts leaves them without defences and hence the LTD deficit provoked by the drug becomes chronic. This permanent absence of synaptic plasticity would explain why drug seeking behaviour becomes resistant to environmental constraints (difficulty in procuring the substance, adverse consequences of taking the drug on health, social life, etc.) and consequently more and more compulsive. Gradually, control of the taking of the drug is lost and addiction appears.

New Treatment for Addiction?

For Pier-Vincenzo Piazza and his collaborators, these discoveries also have important implications for developing new treatment of addiction. “We are probably not going to find new therapies by trying to understand the modifications caused by a drug in the brains of drug addicts,” explain the researchers, “since their brain is anaplastic.”

For the authors, “The results of this work show that it is in the brain of the non-addicted users that we will probably find the key to a true addiction therapy. Indeed,” the authors estimate, “understanding the biological mechanisms which enable adaptation to the drug and which help the user to maintain a controlled consumption could provide us with the tools to combat the anaplastic state that leads to addiction”.

The nature-nurture debate is usually about how much of something is due to our genes and how much is caused by our environment. New research just published in the academic journal Addiction shows that the case is more interesting for young women who smoke, drink, or use drugs, for two related reasons.

First, a young woman with a genetic predisposition to substance use is also predisposed to choose friends who smoke, drink, or use drugs, thereby altering her environment in a way that encourages substance use. Second, a young woman’s exposure to substance-using friends not only changes her environment but also increases her genetic inclination to use these drugs regularly, thereby raising even higher her already increased likelihood of substance use.

Friends Influence Substance Abuse

Using a sample of over 2,000 female twins, researchers from Washington University in St. Louis looked for links between two types of data: 1) women in the sample who regularly used tobacco, alcohol, or drugs and 2) women whose friends were involved in regular substance use. The links they found showed that genetic vulnerability to regular use of alcohol, cigarettes and cannabis is exacerbated by exposure to friends who use alcohol, cigarettes and drugs.

It is well known that adolescents often select peers who engage in behaviors similar to their own. But this study showed that peer selection has a genetic basis whereby one’s genetic predisposition to regular substance use is correlated with the likelihood of choosing friends who also use psychoactive substances. The genetic factors that influence our own likelihood of using drugs thus also modify our likelihood of associating with friends who do the same.

Interited Factors

However, exposure to these drug-using peers has a second, important influence on our own liability to use drugs. The study found that heritable influences on an individual’s own regular substance use increased as they affiliated with more drug-using peers – in other words, affiliations with substance-using peers enhances the role that heritable factors play in our own regular substance use. Put simply, increasing affiliations with drug-using peers is correlated with a more ‘genetic’ form of regular substance use.

According to lead author Dr. Arpana Agrawal, “Nature and nurture don’t just combine to produce a woman who smokes, drinks, or uses drugs – nurture can also increase the effect of nature.”

A new study from Karolinska Institutet presents a new technique that makes drug testing possible through exhaled air for the first time. By examining people who had received emergency care for an amphetamine overdose, the researchers found that in all cases there were traces of amphetamine and metamphetamine in the exhaled breath.

“Traditionally, drugs tests have been carried out using urine and blood samples,” says Professor Olof Beck, who led the study. “In recent years we’ve been trying to find simpler alternatives using saliva, which, unfortunately, has proved difficult. Our results open the way for a new kind of drugs test, which is simple and safe to conduct and that requires no integrity-violating monitoring or medical staff.”

Reliable Drug Tests

Drug abuse is a huge social problem and drugs tests are used widely and comprehensively by the healthcare and social services, the legal system, at workplaces and schools. Reliable drugs tests are important for making correct diagnoses and for keeping tabs on drug users to ensure that they are following prescribed treatment. Alcohol can easily be checked in a breathalyser, and the technology is available for conducting measurements in a way that doesn’t violate a person’s integrity. Measurements of other substances in the exhaled breath are available for diagnosing diseases such as asthma and diabetes.

In this present study, which is published in the latest issue of The Journal of Analytical Toxicology, scientists at Karolinska Institutet have developed a new and unique method for collecting narcotic substances from the exhaled breath. This they did by asking subjects to breathe into a specially designed mask for ten minutes, whereupon the exhaled air was collected and passed through a filter, which trapped the narcotic substances. These filters were then analysed using combined liquid chromatography and tandem mass-spectrometry, techniques that are highly sensitive and reliable.

The researchers took samples from 12 patients who had been admitted into emergency care with toxic symptoms after having taken amphetamines. The samples were taken after the effects of the drug had worn off and with the permission of the regional ethical review board in Stockholm. The ingestion of the drug was confirmed in the patient group through urine and blood samples. In all cases, the researchers were able to ascertain the presence of amphetamine and metamphetamine (a narcotics-classed central-stimulating substance similar to amphetamine) in the exhaled breath as well. The measured excretion rate was between 0.2 and 139 pg/min, which is very low compared to the blood and urine. No amphetamine or metamphetamine were detected in samples from healthy controls.

Drugs In Exhaled Breath

“The results are convincing and very promising,” says Professor Beck. “The study is the first to report the possibility of measuring drugs in the exhaled breath, and represents a unique, unexpected finding. We now have to move on to other drugs that are of interest for this type of breath test, and to develop the sampling and analysis methods. An instrument like a breathalyser for drugs would be the optimal solution for the efficient control of drug use by motorists, for example.”

The study was conducted by researchers at the clinical pharmacology division of the Department of Medicine, Solna and at the Psychiatry Unit at the Department of Clinical Science, Karolinska Institutet, and was financed by Vinnova (the Swedish Governmental Agency for Innovation Systems), the Stockholm County Council and the Swedish Research Council.

As fewer people puff on cigarettes, a new smoking trend may be gaining popularity among North American youth. A study published in the journal Pediatrics has found that almost one-quarter of young adults in Montreal had used waterpipes (also known as shishas or hookahs) in the past year.

“The popularity of waterpipes may be due in part to perceptions that they are safer than cigarettes. However, waterpipe smoke contains nicotine, carbon monoxide, carcinogens and may contain greater amounts of tar and heavy metals than cigarette smoke,” warns senior investigator Jennifer O’Loughlin, a professor at the University of Montreal Department Of Social and Preventive Medicine and a scientist at the University of Montreal Hospital Research Center.

Hookahs Popular Among Males

As part of a longitudinal cohort investigation (NDIT Study), 871 youth aged 18 to 24 completed questionnaires on their smoking habits. The research team, which included scientists from the University of Montreal, the National Institute of Public Health of Quebec and McGill University, found that 23 percent of respondents had used a waterpipe within the last 12 months and that 5 percent had used waterpipes one or more times in the past month.

The study found waterpipes to be particularly popular among young, English-speaking males who lived on their own and had a higher household income. In addition, the research team found that waterpipe users were more likely to use other psychoactive substances such as cigarettes, marijuana, illicit drugs and alcohol.

Some of the same brain mechanisms that fuel drug addiction in humans accompany the emergence of compulsive eating behaviors and the development of obesity in animals, according to research funded by the National Institute on Drug Abuse (NIDA), a component of the National Institutes of Health.

The study, conducted by researchers at the Scripps Research Institute, was released today in the online version of Nature Neuroscience and will also appear in the journal’s May 2010 print issue. When investigators gave rats access to varying levels of high-fat foods, they found unrestricted availability alone can trigger addiction-like responses in the brain, leading to compulsive eating behaviors and the onset of obesity.

Addiction and Obesity

“Drug addiction and obesity are two of the most challenging health problems in the United States,” said Dr. Nora D. Volkow, director of NIDA. “This research opens the door for us to apply some of the knowledge we have gathered about drug addiction to the study of overeating and obesity.”

Both obesity and drug addiction have been linked to a dysfunction in the brain’s reward system. In both cases overconsumption can trigger a gradual increase in the reward threshold—requiring more and more palatable high fat food or reinforcing drug to satisfy the craving over time.

Researchers conducted this study in three groups of male rats over a 40-day period. Each day, the three groups had unlimited access to standard lab food. In addition, two of the groups also had access to high-fat, cafeteria style foods for short (one-hour) or long (18-23 hours) periods.

After 40 days, all groups were denied access to the high-fat foods. Throughout the study, researchers observed the feeding behaviors of each group, noting caloric intake, weight gain, and brain response.

The results support the notion that type 2 dopamine receptors (D2DR)—brain receptors that have been shown to play a key role in addiction—also play a key role in the rats’ heightened response to food. In fact, as the rats became obese, the levels of D2DR in the brain’s reward circuit decreased. This drop in D2DR is similar to that previously seen in humans addicted to drugs like cocaine or heroin.

Insight Into Obesity

“The results of this study could provide insight into a mechanism for obesity,” said Paul J. Kenny, one of the study’s co-authors and an associate professor at the Scripps Jupiter, Fla., research facility. “It’s possible that drugs developed to treat addiction may also benefit people who are habitual overeaters.”

Study results also suggest that environmental factors, such as increased or unlimited access to high-fat food options, can contribute to the problem of obesity.

“Hopefully, this study will change the way people think about eating,” said Paul Johnson, a co-author and graduate student in the department of molecular therapeutics. “It demonstrates how just the availability of food can trigger overconsumption and obesity.”

In the last month, Anthony Scalzo, M.D., professor of toxicology at Saint Louis University, has seen nearly 30 cases involving teenagers who were experiencing hallucinations, severe agitation, elevated heart rate and blood pressure, vomiting and, in some cases, tremors and seizures. All of these teens had smoked a dangerous, yet legal substance known as K2 or “fake weed.”

According to Scalzo, K2, an unregulated mixture of dried herbs, is growing in popularity because it is legal, purported to give a high similar to marijuana and believed to be natural and therefore safe.

Many Adverse Effects

“K2 may be a mixture of herbal and spice plant products, but it is sprayed with a potent psychotropic drug and likely contaminated with an unknown toxic substance that is causing many adverse effects. These toxic chemicals are neither natural nor safe,” said Scalzo, who also directs the Missouri Regional Poison Control Center at SSM Cardinal Glennon Children’s Medical Center.

What makes K2 so dangerous? Further testing is needed, but Scalzo says the symptoms, such as fast heart beat, dangerously elevated blood pressure, pale skin and vomiting suggest that K2 is affecting the cardiovascular system of users. It also is believed to affect the central nervous system, causing severe, potentially life-threatening hallucinations and, in some cases, seizures.

While JWH 018, a synthetic man-made drug, similar to cannabis, may be responsible for the hallucinations, Scalzo suspects that there is another unknown toxic chemical being sprayed on K2.

Mixture is Not ‘Natural’

K2, also known as “spice,” has been sold since 2006 as incense or potpourri. It sells for approximately $30 to $40 per three gram bag, which is comparable in cost to marijuana, and is available over the Internet.

“K2 use is not limited to the Midwest; reports of its use are cropping up all over the country. I think K2 is likely a bigger problem than we’re aware of at this time,” Scalzo said.

Legislators in Missouri currently are considering a proposed ban of K2, which Scalzo supports. In the meantime, he says that parents should be on the lookout for warning signs such as agitation, pale appearance, anxiety or confusion due to hallucinations.

“Look for dried herb residues lying around your kids’ room. Chances are they are not using potpourri to make their rooms smell better or oregano to put on their pizza,” Scalzo said.

Young adults who have used cannabis or marijuana for a longer period of time appear more likely to have hallucinations or delusions or to meet criteria for psychosis, according to a report posted online today that will appear in the May print issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

Previous studies have identified an association between cannabis use and psychosis, according to background information in the article. However, concerns remain that this research has not adequately accounted for confounding variables.

Cannabis Use and Psychotic Outcomes

John McGrath, M.D., Ph.D., F.R.A.N.Z.C.P., of the Queensland Brain Institute, University of Queensland, Australia, and colleagues studied 3,801 young adults born between 1981 and 1984. At a 21-year follow-up, when participants were an average age of 20.1, they were asked about cannabis use in recent years and assessed using several measures of psychotic outcomes (including a diagnostic interview, an inventory of delusions and items identifying the presence of hallucinations).

At the 21-year follow-up, 17.7 percent reported using cannabis for three or fewer years, 16.2 percent for four to five years and 14.3 percent for six or more years. Overall, 65 study participants received a diagnosis of “non-affective psychosis,” such as schizophrenia, and 233 had at least one positive item for hallucination on the diagnostic interview.

Among all the participants, a longer duration since the first time they used cannabis was associated with multiple psychosis-related outcomes. “Compared with those who had never used cannabis, young adults who had six or more years since first use of cannabis (i.e., who commenced use when around 15 years or younger) were twice as likely to develop a non-affective psychosis and were four times as likely to have high scores on the Peters et al Delusions Inventory [a measure of delusion],” the authors write. “There was a ‘dose-response’ relationship between the variables of interest: the longer the duration since first cannabis use, the higher the risk of psychosis-related outcomes.”

Not a Simple Connection

In addition, the researchers assessed the association between cannabis use and psychotic symptoms among a subgroup of 228 sibling pairs. The association persisted in this subgroup, “thus reducing the likelihood that the association was due to unmeasured shared genetic and/or environmental influences,” the authors continue.

“The nature of the relationship between psychosis and cannabis use is by no means simple,” they write. Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently. “This demonstrates the complexity of the relationship: those individuals who were vulnerable to psychosis (i.e., those who had isolated psychotic symptoms) were more likely to commence cannabis use, which could then subsequently contribute to an increased risk of conversion to a non-affective psychotic disorder.”

The findings should encourage further research to elucidate the mechanisms underlying the relationship between psychosis and cannabis use, the authors conclude.