Study Probes Military’s “Culture of Binge and Underage Drinking”

Problems continue after active duty.

A University of Minnesota study found a level of underage binge drinking in the military that the study’s lead author called “dangerous to both the drinkers and those around them.” Mandy Stahre, the epidemiologist who headed up the study, said the results were disturbing, “given the equipment and dangerous environments commonly encountered by active duty military personnel.”

The article, “Binge Drinking Among U.S. Active-Duty Military Personnel,” appears in the March issue of The American Journal of Preventative Medicine. Researchers at the University of Minnesota and the Centers for Disease Control analyzed the results of an anonymous health survey of 16,000 military personnel conducted in 2005. (The group defined binge drinking as four or more drinks in one session for men, and three or more drinks for women.) In an interview with a University of Minnesota radio station, Stahre said that 43 percent of the active respondents reported binge drinking in the past month. Stahre said the figure represents “a total of 30 million episodes of binge drinking, or 32 episodes of binge drinking per person per year.” 5 million of those episodes, Stahre said, involved active duty personnel under the age of 21.

These figures are scarcely surprising, but the implications are no less nerve-wracking. Stahre said military binge drinkers were five times more likely to drive while drinking, compared to non-binge drinkers. Moreover, binge drinking is chronically under-reported in the military, Stahre said, cautioning that the conclusions in the study “may be conservative.” She called for an increase in alcohol excise taxes, stricter military enforcement of a minimum drinking age of 21, and “greater efforts at screening and counseling for alcohol misuse” in the military.

What can a study of this nature accomplish? Stahre said she hopes it will provide “further evidence that binge drinking is a major public health problem in the U.S. and in the military. And the military may be in a unique position to help reduce this problem in the general population, particularly given that nearly 13 percent of U.S. adults report current or past military service.”

Last summer, a study published in the August 13 issue of the Journal of the American Medical Association (JAMA) demonstrated that Reserve and National Guard combat personnel returning from the wars in Iraq and Afghanistan were at increased risk for “new-onset heavy drinking, binge drinking and other alcohol-related problems.” The article also found a strong association between posttraumatic stress disorder (PTSE) and substance abuse among returning veterans.

photo credit: http://navyformoms.ning.com/

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Marijuana Legalization Is Coming, Says Pollster

Nate Silver reads the numbers.

Last month, I missed this crucial article, penned by the inestimable Nate Silver. Silver, you may recall, is the numbers nerd who shamed all conventional pollsters during the run-up to the presidential election—and then proceeded to predict the Electoral College vote with perfect accuracy.

So when Nate Silver takes a hard look at statistics having to do with American sentiment about marijuana legalization, it behooves us to take his findings seriously. In an April 5 post called “Why Marijuana Legalization is Gaining Momentum,” on his FiveThirtyEight.com blog, Silver lays out the inevitable chronology.

“Back in February, we detailed how record numbers of Americans -- although certainly not yet a majority -- support the idea of legalizing marijuana,” Silver writes. “It turns out that there may be a simple explanation for this: an ever-increasing fraction of Americans have used pot at some point in their lifetimes.”

According to Silver’s number crunching, the peak pot year in anyone’s life is on or about age 20—duh—with most people reaching some sort of usage plateau between the ages of 30 and 50. The important point, Silver writes, has to do with the fraction of adults who have used. This is a dual-peaked distribution, “with one peak occurring among adults who are roughly age 50 now, and would have come of age in the 1970s, and another among adults in their early 20s. Generation X, meanwhile, in spite of its reputation for slackertude, were somewhat less eager consumers of pot than the generations either immediately preceding or proceeding them.”

Furthermore, reports of lifetime usage drop off precipitously after 55. “About half of 55-year-olds have used marijuana at some point in their lives, but only about 20 percent of 65-year-olds have.”

What does this tell us? While there is certainly not an exact correspondence between people who have smoked pot and people who support legalization, Silver ventures to guess that the link is fairly strong. What we have here, he argues, is a “fairly strong generation gap when it comes to pot legalization. As members of the Silent Generation are replaced in the electorate by younger voters, who are more likely to have either smoked marijuana themselves or been around those that have, support for legalization is likely to continue to gain momentum.”

Photo: Minnesotaindependent.com

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Addiction Assumptions: The Meth Epidemic

Who is really at risk?

A simple question: Has meth use in the United States truly reached “epidemic” levels, as is commonly stated by health authorities and drug experts?

The answer depends on how you slice the data, according to sociologist Herbert Covey. For women, unemployed men, and residents of the Western United States, the answer is yes. For African-Americans and citizens of the Northeast, not so much.

In “Prevalence of Use and Manufacture of Methamphetamine in the United States,” published in the Praeger International Collection on Addictions, Dr. Covey first notes that the spread of methamphetamine use is by no means unique to the United States. In Thailand, Covey writes, more than 70 percent of the addict population is composed of meth users.

In the U.S., meth lab busts increased 4,000 percent from 1995 to 2001, according to the Office of National Drug Control Policy. Treatment numbers also soared, but it is not clear whether this trend represents more meth users, or more court-mandated treatment for offenders.

The short answer to the question of who is at primary risk is: women. According to Covey, women of childbearing age represent a severely problematic risk group. Women report using meth at an earlier age, have significantly longer first treatment experiences, and have greater difficulty than men with related issues of employment, child-raising, and job opportunities. (See my post on “Rehab and the Working Mother.”)

Perhaps the most unwelcome finding of all is that “The majority of women [in a major study of gender differences] had children under 18, but most did not live with their children within the last 30 days.”

However, there is a tendency in the media to leap ahead of the data with stories of this sort. Covey and other researchers question the validity of media references to “meth babies” and “ice babies,” recalling the overblown coverage of the “crack baby” epidemic of the 1980s—an epidemic for which, more than two decades later, there is almost no solid evidence. As Covey cautions, “that meth use by pregnant women results in severe health consequences for infants has not been established by medical research.”

As Covey sums it up: “Meth accounts for a small percentage of the total number of people affected by drug and alcohol problems. However, almost all of the data... reveal that meth use, manufacturing and distribution are increasing throughout much of the nation.” In the future, he writes, “The other question is whether meth use will grow in prevalence in minority populations. To date Latino, Hispanic, and African American populations have not embraced meth to the extent that Anglos have. If this changes, the negative effects could be substantial.”

Covey concludes: “Whether the upward spiral of meth use and manufacture continues remains to be seen.”

Photo Credit: The Curvature

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Addiction Assumptions: Denial

Is denial always part of the deal?

Maybe denial really IS just a river in Egypt. Lorraine T. Midanik, dean of the School of Social Welfare at the University of California in Berkeley, is convinced that the contemporary concept of denial as applied to alcoholism represents a weak link in the disease model of addiction.

Neither the founding fathers of Alcoholics Anonymous, nor the foremost early proponent of the disease model—E.M. Jellinek—specifically identified denial as a core concept of alcoholism, according to Midanik. In “The Philosophy of Denial in Alcohol Studies: Implications for Research,” which appears as a chapter in The Praeger International Collection on Addictions, Midanik highlights the conclusion that often results from making a strict association between alcoholism and denial: “There is no room in this perspective for truth telling from the drinker himself.”

The more often and the more energetically a drinker protests against the hypothesis that he is drinking alcoholically, the more telling the proof that the drinker is “in denial” and therefore incapable of rational decision-making about drinking. Clearly, this is exactly the case in many instances. Denial exists. However, Midanik argues that “the definition of denial in alcohol studies has been expanded well beyond its original meaning” to include a host of vaguely Freudian defense mechanisms, including hostility and other forms of negative behavior. Midanik, who is openly skeptical regarding many aspects of the disease model, complains that denial has been broadened into a catchall category “for any behavior that prevents the adoption of the disease model system.”

As the “disease model system” is often presented to patients in various rehab centers around the country, I would tend to agree. But Midanik also questions whether there really exists anything beyond what she labels “tactical denial,” meaning “deceptive maneuvers used by alcoholics to conceal the extent of their drinking.” In such cases, the drinker is obviously aware of what he or she is doing, so the more appropriate term might be “lying.” Nonetheless, I firmly believe that denial, in the sense of lack of self-awareness, or dissociation, is often an acute part of the presenting symptoms of alcoholism, if not quite the “central core of alcoholism treatment,” as Midanik sees it.

Midanik describes something like a cabal of interests helping to foster and inflate the denial concept—AA, Al-Anon, and various codependency groups in particular—even though “study after study and review after review report that alcoholics give valid self-reports....” Here Midanik is onto something interesting. As she intriguingly relates, the near-universal presumption guiding “interventions” or “structured encounters” with supposed alcoholics is that “there is a continuum with denial on one end and truth telling on the other. Overreporting rarely if ever exists.”

Yet overreporting is a well-known issue in clinical research. Midanik refers to the “hello-goodbye effect,” in which patients tend to overemphasize their symptoms when entering treatment, and to minimize them at the end of treatment. If new patients overreport their alcohol consumption, “there are important implications for treatment personnel who base treatment decisions on these self-reports.” Moreover, overreporting may also bias clinical studies “by inflating success rates (presuming there was an opposite bias after treatment). Yet despite the implications of these findings, little interest has been shown by researchers in the alcohol field to explore this area.”

Photo Credit: shatteringdenial.com

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The Alcoholic Rats of Dr. Li.

Excerpt from chapter 1 of The Chemical Carousel.

In the early 1990s, it was safe to say that Dr. Ting-Kai Li was in possession of the largest and most famous collection of alcoholic rats in the world.

Housed in a laboratory near Dr. Li’s office at Indiana University, the “P-line” of rodents were freely self-administering the body-weight equivalent of one bottle of whiskey a day for a 155-pound man; a blood alcohol concentration that would have gotten them arrested on any highway in America. The P-line rats were seriously addicted to ethanol, the purified form of booze known outside the laboratory as grain alcohol, or white lightning.

“It’s actually the only line that’s been well developed in the world,” Dr. Li told me at the time, with justifiable pride. “And it has been developed through genetic selection for alcohol preference.” In other words, Dr. Li did not teach these animals to drink. He didn’t have to.

Dr. Li, who was until recently the Director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA), which is the alcoholism wing of the National Institutes of Health (NIH), made it sound easy: “You take a stock with some genetic heterogeneity in it, and then you test it for drinking behavior, and there will be, say, two or three out of a hundred that like to drink, so you take those, and you breed them. And the ones that don’t like to drink, you breed those, and within ten generations you start to have a very good separation between drinking scores.”

Why would a rat drink alcohol, and why would anybody care? When I first spoke with Ting-Kai Li, the lack of suitable animal models of alcoholism and addiction was all too apparent. Without suitable strains of test animals, most genetic and neurobiological research would take centuries, and would involve ethical questions about human testing far stickier than the questions raised by the animal rights movement. Animal models are one of the primary pathways of discovery available to neurobiologists and other researchers.

The precisely spoken, self-effacing Dr. Li, along with neurobiology professor Dr. William McBride and their co-workers at Indiana University, were never really in the business of teaching rats to drink. They were in the business of discovering ways to make them stop.

To be like human alcoholics, the rats must also demonstrate both an increased tolerance to the effects of the drug, and the onset of physical dependence as manifested by withdrawal symptoms. And they do. The P-line rats develop tolerance, and they show acute withdrawal symptoms when researchers cut off their supply. The rats suffer tremors, seizures, and a rodent version of delirium tremens. They fall down a lot. They are also quick to avail themselves of a little “hair of the dog.” After a period of abstinence, they take alcohol again to relieve the withdrawal symptoms.

The P-line rats met every definition of alcoholism anyone could imagine, and the cause of their alcohol addiction appears to be strictly genetic. What was happening with the P-line rats was not explainable by resorting to arguments about simple learned behavior.

“How do you explain this difference?” said Dr. Li, all those years ago. “My explanation is that there are genetic differences among different individuals. You’re making the assumption that you expose them to the same environment, the same environmental influences, and yet they behave differently in terms of addiction.”

Today, we can safely say that Dr. Li’s hypothesis has proven to be true.

© Copyright 2008

Photo Credit: smh.com.au

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Addiction: The First Taste

From the introduction to The Chemical Carousel.

It was the late 1980s, and the “Decade of the Brain,” sponsored by the National Institute of Mental Health (NIMH) and the Library of Congress, was still a few years away. I was sitting in a Clement Street diner in San Francisco, reading a book called The Hidden Addiction, by a Seattle M.D. named Janice Keller Phelps, and trying to understand why I could not stop drinking. Dr. Phelps was saying that most of what I thought I knew about alcoholism and other addictions was completely wrong.

Years earlier, I had written a nonfiction book about the rise of Silicon Valley, so I was under no illusions about the scientific learning curve involved in writing a book about the dawn of addiction medicine. But I had the means and the motivation: a background as a science and technology journalist, and a solid addiction to alcohol and cigarettes.

We’re in Junior High, Randy and I, and it’s the weekend. We’re staying at Randy’s, after a successful performance at a state swimming meet, and Randy’s parent’s are out for the night. A typical sleepover, stupid movies and all the cokes you can drink.

But this Saturday night turned out differently, and to this day I can’t really say why. I remember Randy showing me his dad’s stash of liquor bottles underneath the kitchen sink, and us laughing about it, and what would you pick, Scotch or Gin, and what the hell was Vermouth?

Amazingly, I don’t recall what we picked, or exactly how much of it we drank. I remember that it went down okay, with the usual spluttering, and it was giggly and light-headed and fun.

And then, in my memory, a long, blurred period of time passing, and a sense of coming back into my body on a bed I did not recognize, face turned to the wall, Randy moaning quietly beside me. It was a sort of rolling blackout, sweet oblivion, the only one I have ever experienced. Suspended in time, as lost to ordinary chronology as I have ever been, before or since. And strangely, for all the drinking to come, I was never a blackout drinker again. No lost weekends, and no lost cars, dude.

“Come on,” I remember saying to my friend, as I came unsteadily to consciousness on the rocking bed, “let’s go have some more.” Unbelievable. Randy and I had already drunk ourselves into a stupor.

Let’s have some more. Good idea.

And then Randy saying, “Hi, mom,” in the way you say it when you’re trying to freak out your buddy and there’s nobody really there, like looking over his shoulder and pretending to see somebody when your buddy is copping a quick piss in the bushes, and saying in a deep voice, “Hi there, sir, how’s it going?” Just to watch him fumble with his zipper in a panic. So I roll over on the bed toward Randy, saying “Yeah, right, Randy, like I’m falling for that,” and in that instant seeing Randy’s mom standing speechless in the doorway of what turned out to be the master bedroom. Staring at us with shock. Or maybe I was the one who went into shock, as I remember very little of the rest of it. At some point Randy’s mother called my mother, naturally, despite my fervent prayers designed to produce an intercession, and my dad drove over and took me home, where I fell asleep (it was Saturday) for most of the day. I woke up feeling like hammered dogshit, as they say. My father was sitting in a chair in my bedroom. “Well,” he said, when I was as awake as I was going to get, “did you learn anything from this?”

Years later, I came across a study in the Archives of Pediatrics and Adolescent Medicine—“Age at Drinking Onset and Alcohol Dependence.” The conclusion of this cross-sectional survey of more than 43,000 adults was stark and straightforward: “Relative to respondents who began drinking at 21 years or older, those who began drinking before age 14 years were more likely to experience alcohol dependence ever and within 10 years of first drinking.”

Randy and I were 13 years old.

--Dirk Hanson

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Bulimia: What To Look For [Guest Post]

Signs and symptoms of a dangerous disorder.

[Today’s guest post was contributed by Heidi Taylor. I include it here as part of a continuing series of guest posts having to do with the so-called “lifestyle addictions,” such as perceived addictions to gambling, sex, video games, or shopping—areas in which I can claim no special expertise, and diagnoses which remain controversial among addiction researchers. However, I do strongly believe that the case has been made for the addictive nature of certain eating disorders—bulimia and carbohydrate-craving obesity in particular—in which the ingested substance is food, not “drugs” as we commonly think of them. Eating is one of the most obvious ways in which we alter the neurochemistry of our brains every day. As for treatment, serotonin abnormalities are believed to be the culprit. Many bulimics improve on SSRI antidepressants.]
--Dirk Hanson

Detecting Bulimia in a Loved One

It’s not a disease that’s visible at first or even second sight, but even so, it is one that’s largely ignored and left untreated more because most people are not even aware of its existence. But bulimia, or to be exact, bulimia nervosa is an eating disorder that could end up having physical, psychological and sociological consequences that are hard to digest. Bulimics tend to eat more than they should – in fact, they gorge on food – and then force themselves to throw up using emetics, visit the toilet with laxatives, or go without food for the next day or so. In short, they compensate for their over-eating in ways that are neither healthy nor advisable.

While it may not seem like a dangerous disorder, bulimia can have devastating consequences if left unchecked – people affected are prone to suffer from an inflamed throat and neck glands, a torn esophagus, decaying and unhealthy teeth, acid reflux disorder, ruptured intestines, irritable bowels, dehydration and malfunctioning kidneys. Besides these physical symptoms, they’re also going to be obsessed with their weight, suffer from depression and anxiety, and face other mental and social problems. So if you suspect a loved one may be bulimic, here are a few symptoms that will help you detect the disorder and get them professional help as soon as possible:

• Eating more than the normal amount possible in a single meal or over the course of a few meals.
• Frequent visits to the toilet after a meal.
• A washed out and drained look that happens because they’re dehydrated and their body is low in minerals from all the purging and use of laxatives.
• Mood swings that seem to come on for no apparent reason.
• Sores in the mouth and/or on their fingers (because they may be sticking it in their throats to induce vomiting).
• Inflamed throats and bad teeth.
• Bouts of depression or uncalled for anxiety attacks.
• Exercising for a long time, at odd hours of the day and being obsessed with the way they look.
• It’s the women and the teenagers who are more susceptible to this disorder because of their obsession with their weight and the way they look. So if you have a daughter or a close female friend or relative who acts in a way that points suspicion to bulimia, talk to them and get them much-needed medical intervention before the situation worsens.

Even if you just suspect bulimia and are not really sure, you’d do well to talk to the person concerned and get them to see a doctor who can help. Remember, it may sound like a minor thing, but bulimia is a very serious disorder.
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This post was contributed by Heidi Taylor, who writes about the Masters in Healthcare. She welcomes your feedback at HeidiLTaylor006 at gmail.com

Graphics Credit: Graham Menzies Foundation

Phish Front Man Backs Drug Courts

Trey tells Congress about his addiction.

Trey Anastasio, lead guitarist and singer with the recently reunited rock band Phish, testified before Congress that drug courts may have saved his life. Without drug courts, he said, there might not have been a Phish reunion tour. Their lead guitarist might have been dead or in jail.

“My name is Trey Anastasio, and I’m a recovering alcoholic and a proud graduate of the Washington drug court program,” the musician testified, according to a Huffington Post report by Ryan Grim. “My life had become a catastrophe. I had no idea how to turn it around. My band had broken up. I had almost lost my family. My whole life had devolved into a disaster. I believe that the police officer who stopped me at three a.m. that morning saved my life.”

Anastasio, on behalf of the National Association of Drug Court Professionals (NADCP), called for drug courts as an alternative to prison for every American in need. Participants in drug courts receive mandated addiction treatment and other services, while submitting to regular drug tests. Those who fail their drug tests spend time in prison. Moreover, participants appear regularly before a specially trained judge to access their progress. A system of rewards and sanctions, plus treatment, replaces a lengthy jail sentence and little hope for effective treatment while imprisoned.

In the past, while supporting the concept, Congress has made only meager sums available for the establishment of drug courts. “I would like every community in America to have the option of sentencing drug offenders to drug court,” Anastasio told members of Congress. “When we imprison people for minor drug offences, we waste money—and we waste lives. Prison will turn a person with a substance abuse problem into a lifetime felon.”

According to NADCP chief executive officer West Huddleston, “The scientific community has put drug courts under the microscope and concluded that drug courts significantly reduce drug abuse and crime and do so at less expense than any other justice strategy.”

Anastasio, who spend more than a year in drug court, told the congressional assembly that he had been sober for two and half years. “In August, my wife and I will celebrate our fifteenth wedding anniversary. My band is back together with a sold-out tour. And in September I’ll play a solo concert at Carnegie Hall with the New York Philharmonic.”

Photo Credit: WPT

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Acupuncture for Addiction: It Doesn't Look Good

Needles fail in latest study of opiate detox.

Acupuncture as a treatment for drug addiction took another punch recently in a study published in the Journal of Substance Abuse Treatment. In “Auricular acupuncture as an adjunct to opiate detoxification treatment,” the study authors investigated whether acupuncture would “add value” to a standard methadone-based detoxification process. For the two-week study, 82 opiate-addicted patients were randomly assigned to either ear acupuncture by qualified acupuncturists, or the attachment of ear clips by non-professionals. Each day, the study participants were tested for withdrawal severity and craving.

"On none of the 14 days,” the authors report, “were there statistically significant differences between patients allocated to ‘real’ acupuncture and the ‘sham’ treatment. Such statistically insignificant difference as there were favored the ‘sham’ treatment....”

The results, say the authors, “are consistent with the findings of other studies which failed to find any effect of acupuncture in the treatment of drug dependence.” Moreover, the authors conclude, this finding is “particularly disappointing as if anything the circumstances favored the acupuncture option,” since in contrast “the alternative may not have been seen as a convincing therapy.” Nevertheless, “like the featured study, previous studies of acupuncture in the treatment of opiate addiction have been unconvincing.... The ‘ineffective’ verdict on acupuncture extends to the treatment of cocaine dependence,” the authors maintain, while an attempt to replicate earlier positive findings on acupuncture for alcohol dependence found no benefits, either.

The authors also reflect on whether such offerings, though of dubious value, attract addicts to treatment centers. “The possibility remains that offering something concrete like acupuncture helps attract people to services, and that doing something both clients and staff believe is worthwhile (even if it is a ‘sham’ procedure) helps retain patients in treatment, and in doing so improves outcomes.”

Of course, this is only one study out of many, and acupuncture enthusiasts remain as optimistic as ever. Proponents of acupuncture treatment continue to petition the National Institute on Drug Abuse (NIDA) for endorsement. Most reports of success remain anecdotal. Nonetheless, the National Acupuncture Detoxification Association estimates that there are currently 200 acupuncture detoxification programs operating in the United States and Europe.


Photo Credit: The 217

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Guest Post: Things Go Better with Meth

The Pepsi Challenge with controlled substances.

[Today’s post comes to us from Neurological Correlates, a blog devoted to the neuroscience of dysfunctional behavior. It was written by Swivelchair, who refers to himself as “an anonymous biopharma worker." It’s an excellent blog, one of the few that focuses on the biological basis of addiction.]
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Things go better with meth, as compared to cocaine, if you’re dopamine transporter challenged, anyway.

By Swivelchair

Methamphetamine is taken up more quickly, and lasts longer than cocaine. (Fowler et al, Abstract below).

And here’s something from Microgram Bulletin, October 2008, Published by the Drug Enforcement Administration Office of Forensic Sciences Washington, D.C. 20537: The DEA South Central Laboratory (Dallas, Texas) recently received a submission of approximately 4972 fake “kidney beans” (total net mass 3,210 grams), all containing a fine tan powder, suspected heroin. The “beans” were actually small plastic packets that had been painted to resemble kidney beans... Analysis of the powder... confirmed 90.3% heroin hydrochloride.

The perhaps undeniable point: probably the self-selecting population of people who are first drawn to drugs, and then become irretrievably addicted, are those who lack sufficient dopamine transport to feel fulfilled (or other insufficiency, depending on the choice of drug). They are, in essence, self-medicating, rather than using drugs for recreational use. I mean, you don’t load up kidney beans for recreational drug users.

I’m reminded of a friends’ younger brother, from a locally well-known family, whose arrest was reported as bringing in “the largest amount” of cocaine in those parts. His remark: He was a wholesaler, and the newspaper quoted street (”retail”) values, so the report inflated his inventory value. This was purely about money for him — he made far more money selling coke than any job he was qualified to do (which was, well, probably none, unless being a bon vivant and sparkling raconteur with insufficient money to fund a high rent party lifestyle qualifies as a profession, which it may). If the US were to decriminalize drug use, and fund a program to make an agonist which was not addictive (a la the whole methadone thing), probably we could solve much of the crime problem in the Western Hemisphere.
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“Fast uptake and long-lasting binding of methamphetamine in the human brain: comparison with cocaine.” Fowler JS, Volkow ND, Logan J, et. al. Medical Department, Brookhaven National Laboratory, Upton, NY 11973

Abstract from Neuroimage. 2008 Dec; 43(4):756-63.

“Methamphetamine is one of the most addictive and neurotoxic drugs of abuse. It produces large elevations in extracellular dopamine in the striatum through vesicular release and inhibition of the dopamine transporter. In the U.S. abuse prevalence varies by ethnicity with very low abuse among African Americans relative to Caucasians, differentiating it from cocaine where abuse rates are similar for the two groups. Here we report the first comparison of methamphetamine and cocaine pharmacokinetics in brain between Caucasians and African Americans along with the measurement of dopamine transporter availability in striatum.

Methamphetamine’s uptake in brain was fast (peak uptake at 9 min) with accumulation in cortical and subcortical brain regions and in white matter. Its clearance from brain was slow (except for white matter which did not clear over the 90 min) and there was no difference in pharmacokinetics between Caucasians and African Americans. In contrast cocaine’s brain uptake and clearance were both fast, distribution was predominantly in striatum and uptake was higher in African Americans. “Among individuals, those with the highest striatal (but not cerebellar) methamphetamine accumulation also had the highest dopamine transporter availability suggesting a relationship between METH exposure and DAT availability. Methamphetamine’s fast brain uptake is consistent with its highly reinforcing effects, its slow clearance with its long-lasting behavioral effects and its widespread distribution with its neurotoxic effects that affect not only striatal but also cortical and white matter regions. The absence of significant differences between Caucasians and African Americans suggests that variables other than methamphetamine pharmacokinetics and bioavailability account for the lower abuse prevalence in African Americans.”

Related Links

PET studies of d-methamphetamine pharmacokinetics in primates: comparison with l-methamphetamine and ( –)-cocaine. [J Nucl Med. 2007] PMID:17873134

Long-term methamphetamine administration in the vervet monkey models aspects of a human exposure: brain neurotoxicity and behavioral profiles. [Neuropsychopharmacology. 2008] PMID:17625500

Graphics Credit: methamphetaminetx.com

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