Review Questions Warnings About Meth's Mental Effects


Doctors prescribe methamphetamine and similar stimulants to improve alertness, attention, and mental acuity. Yet anti-drug propaganda (see above) warns that meth, when consumed without a prescription, impairs thinking and ravages the brain, leading to irrational, disordered, self-destructive, and possibly violent behavior. Does a slip of paper from an M.D. magically transform the properties of this chemical? Or should the warnings about meth-related cognitive impairment be taken with a shaker full of salt? 

The latter, suggests a new research review published by Neuropsychopharmacology. Columbia University psychologist Carl L. Hart and three co-authors report that laboratory experiments generally "show that short-term, acute methamphetamine [consumption] improves cognitive performance of both methamphetamine abusers and non-users in some domains, for example, visuospatial perception, sustained attention, and response speed, even when larger intranasal and intravenous doses are tested." As for long-term effects, "statistically significant differences between methamphetamine users and control participants have been observed on a minority of measures" in studies using brain imaging and cognitive tests. But Hart et al. caution that "the clinical significance of these findings may be limited because cognitive functioning overwhelmingly falls within the normal range." Despite a lack of evidence regarding the practical significance of these results, "researchers frequently interpreted any brain differences as indicative of cognitive pathologies caused by the abuse of methamphetamine." Indeed, "many researchers in this area begin with the assumption that methamphetamine abusers exhibit cognitive dysfunction, and that their research bears this out." Noting that methamphetamine offenses are punished especially severely, partly because of the stimulant's allegedly devastating impact on the brain, Hart and his colleagues caution against repeating the errors that led to draconian crack cocaine penalties, based on misconceptions about that drug's purportedly unique hazards:

This prevailing assumption [that meth causes brain damage] has provided the fuel for a growing number of neuroimaging studies assessing the impact of prenatal methamphetamine exposure. Hopefully, more caution will be exercised when interpreting these findings than was exercised when results were interpreted from studies of infants prenatally exposed to cocaine, who were erroneously and too readily condemned to a life of learning disabilities, psychological disturbances, and crime….

It is only recently that penalties associatedwith crack cocaine violations were reduced. This change came after nearly 25 years of criticism of the law because it was inconsistent with the scientific evidence and it exaggerated the harms associated with crack cocaine use. The monetary and human costs of this misunderstanding are incalculable….

Many of the claims about methamphetamine-associated cognitive impairments are reminiscent of statements made about crack cocaine more than two decades ago before the empirical evidence was clear. Taken together, these observations lead us to speculate whether we are headed down this path once again.

Six years ago in Reason, I noted nascent alarm about "meth babies." In a 2005 column, I highlighted over-the-top warnings about meth.

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  1. We have an obligation to lie about the dangers of drugs to make sure kids do not use dangerous drugs.

    1. Helps keep the profit margin up too. BTW, the guy who said to lie to your kids about your past drug use was Clinton.

    2. I don’t know.


      Has the Reason proofreader been using meth?

      1. I don’t know. You do the meth.

        1. with pleasure!

  2. If you use your conclusion as your premise, you will arrive at your conclusion every time!

    Premise: meth causes drain bramage.

    Evidence: Drain bramage exists in meth users.

    Conclusion: meth causes drain bramage!


    This line of reasoning also confirms that AGW is fact and that Keynesian economic policy works.

    1. oops – professor muller got teh madd luv from know-nothing deniers…before muller sanduskied the wingnutz after validating the studies

  3. I have recently lost my meth purity. It was a little distressing to deal with. Be careful about buying rolls. Meth is a dirty, trashy chemical.

    1. jacob’s mistake is ASSUMING purity in street meth.

  4. I don’t know if meth causes mental impairment but from what I saw of meth users during Phoenix’s meth boom a few years back, they can become at best extremely inconsiderate of other people and outright leeches and thieves against their own friends and families.

    End the drug war but that shit is freaky.

    1. they can become…

      Sure they weren’t that way to begin with?

      1. I could see it as a feedback loop.

  5. I think that in a lot of cases, the state of being an addict is more of the cause of health and behavior problems than the actual effects of the drug itself. Particularly the crime and other anti-social behavior.

    1. This.

      Meth or heroin might not cause brain damage, but staying awake for a week while eating nothing but mountain dew and skittles probably does.

  6. Meth, like most drugs, when used in small quantities in a pure, safe form is not dangerous.
    So no, it’s not the “slip of paper from an MD” (way to be sarcastic) that makes the difference.

    It is the purity, and the smaller, controlled dosages that makes the difference.

    1. Duh… Let’s not introduce facts and reason into this thread.

      The ones willing to break the law and use homemade chemicals for a high probably aren’t the moderation types to begin with.

  7. I used meth for a few years in the 1990’s and must unfortunately tell the truth that it was, overall, a positive experience. Met a lot of interesting, fun, crazy, and a few dangerous people.

    As far as hardcore tweakers being fucked up individuals, once you talk to alot of them you find they’ve been that way for a loooong time and for many reasons that have nothing to do with the drug.

    1. Did the “once you talk to alot of them” conversation take place in front of a mirror? 😉

      I’m not buying meth is as safe a prenatal vitamin drug but fuck yourself up if you choose.

      1. Wow, you really are retarded. I was also prescribed methamphetamine (Desoxyn) when I was a kid.

        Seriously, the way people imbue it with great powers (thanks to overstated addiction propaganda) does alot to encourage people to remain in the lifestyle.

    2. Sorry but you’re not the only one who’s dealt with tweekers. No, they’re not all bad.. yet.. give it time. Either they’ll quit or spin out and start lying, stealing, etc…

  8. I would expect that some of the mentally-impaired people using meth were not exactly Mensa candidates at the time they started on the drug.

  9. Just because drugs should be legal, doesn’t mean they aren’t dangerous.

    1. No, but it does imply that statists will exaggerate whatever dangers might be.

    2. This is true. But it is also important to question just how dangerous and in what ways. I don’t think anyone is saying that meth is safe and an OK thing to do. It’s definitely very addictive for many people and anything that allows you to go for days without food or sleep is not going to do a lot of good for your physical wellbeing. But what is caused by the addiction and lifestyle and what is caused by the actual effects of the drug?

      1. The lifestyle is all about ritualized high-dose use, which greatly increases the drug’s effects of insomnia and loss of appetite, as well as contributes to the paranoid thinking that can bedevil illegal drug users.

      2. It’s definitely very addictive for many people

        Just as long as you’re aware that it’s no more addictive than alcohol.

        1. It’s more dopanergic than alcohol, so I doubt that it is true. Even if it is, it doesn’t mean that it isn’t more dangerous than alcohol. At least drunks sleep, and some of them even eat well. Still, both drugs are more toxic than heroin or marijuana, which are technically more illegal.

          1. When studied, percentage addiction difference was less than the error margins.


  10. I take between 20 or 40 mg of Methylphenidate per day, and do well with it.
    I don’t, however take the equivalent dose of 10 times that like the tweakers do.
    Dose rate stupid

  11. The problems hardcore tweakers face are due mainly to the fact they don’t eat or sleep for months on end. That’s going to effect your health.

    1. And I’ve never understood why that’s not obvious to people. Odds are that the majority of smart people you know will go full retard on two subjects: drugs and/or religion.

  12. Hello,
    Thank you for nice writing. It will help me for my research on prescription medications.

  13. Note that other scientists examining meth’s chronic effects have now posted a letter with results that Hart’s group ignored:…..NPP-201204

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