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    When Science Goes To Pot Part II: Evaluations And Perceptions
    By David Sloan | January 2nd 2013 09:40 AM | 44 comments | Print | E-mail | Track Comments
    About David

    David is a neuroscientist in the field of sensory-limbic circuitry. He published his debut novel, [Brackets], in October 2012. He is a member of...

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    I. Preface


    I recently posted an article (Part I) in which I proposed a hypothetical scenario, in which an individual who is offered marijuana takes time out to research the drug exclusively through recent articles on PubMed to see if its a good idea or bad idea. It was meant more as an intellectual exercise, not a commentary or piece of advocacy for either side of the legalization debate (although the commentary after quickly delved into that debate). I wrote the article for the following reasons:
    1. It seemed like a cool idea at the time. 
    2. I don't know very much about the science of marijuana, but I have a neuroscientific and policy-based interest in the topic.
    3. I am interested in how internet search criteria can influence perception and belief on different topics.
    4. I wanted to explore the usefulness of using current peer-reviewed research in making life decisions, since peer-reviewed research is widely considered (I think) our purest source of scientific fact. 


    Posting of the article resulted in a fascinating and wide-ranging commentary about the topic of cannabis, which obviously engenders a lot of strong opinions. From the comments, three main questions/concerns seemed to come up in response to what the article actually said.

    1. In the article, the finding was that the language describing the effect of THC on users in the newest and most accessible literature was very negative. But the regular claim of cannabis users, and the implication of its widespread recreational use, indicate that its use has a positive effect. The discrepancy merits an explanation.
    2. The claim was made that multiple commissions and reports have called for a release of restrictions on marijuana use, based in part on their relative safety, but that these are regularly ignored. This claim merits investigation because, if it is true, then those claims should alleviate concerns for an individual who wants to try it.


    3. It was implied that studies of the effects of THC in lab settings will trend more negative because there is something inherently scary and paranoia-inducing about labs and researchers. The descriptions would be different if the tests were done on beautiful mountaintops or on a sunny beach.

    Herein, I will try to answer the first two issues. I doubt that I'll find much on the third. In keeping with the spirit and structure of the original article, I will continue to search exclusively in primary source material, but I will expand my search to include official commission and government documents on the topic. For those of you who might want to continue this in the fictional vein of the first article, here you go:

    "Jimmy meets up with his friend, who we will call Freddy. Jimmy tells Freddy that he consulted PubMed, and based on what he read, smoking pot sounded like a bad idea. Freddy is amazed and confused, because he really enjoys it. So they decide to go back to Jimmy's computer to dig some more, because neither one could tolerate an unanswered question or logical discrepancy."

    II. The Positive and Negative Effects of THC


    When I started this most recent search, I first found a lot of articles about brain differences in the fMRIs of people who responded differently to 10 mg oral THC (the key differences seem to be the parahippocampal gyrus, medial temporal cortex and cerebellum). Interesting, but not helpful unless Jimmy wants a pre-cannabis MRI. Descriptions of the effects of THC in those papers were identical to those in previous articles: "acute psychosis, increase in measures of anxiety, sedation and intoxication," with no mention of whether or not the subjects liked it.


    After a search that led me through reports by Zvolensky et al (2009, 2010) about increased risk of panic disorder in marijuana users, I found the much more helpful Thomas 1996. In this survey, "light" marijuana users (less than 50 times total) reported that 20% experienced panic attacks, 13% reported psychosis ("strange, unpleasant experiences...hearing voices...paranoia...sense of persecution"), 6% reported their physical health harmed at some point in the history of their use. Across light and heavy users, the risk of panic attacks was significantly greater in women, by 2:1. Of course, all the risk measures go up in heavy users. So based on the survey, the odds of something bad happening (paranoid psychosis or panic) with light users is about 1 chance in 6. The study was done in New Zealand, so you have to take into account differences in hobbit consumption, etc.

    After some more hopping, I was led to an excellent review by Johns 2001 that had some interesting things to say about post-cannabis "acute toxic psychosis". It quoted several international studies in which "appreciable" numbers of people were presenting with  psychotic symptoms post-cannabis. The symptoms were "mild impairment of consciousness, distorted sense of passage of time, dream-like euphoria, progressing to fragmented thought processes and hallucinations, generally resolving within a week of abstinence". 


    Now we're getting somewhere. So, when scientists use the term "psychosis" (which I think anyone will admit is not a pleasant term), it can mean different things. It can be really unpleasant (paranoia, persecution complexes) or it can be pleasant (dream-like euphoria). 

    In the most thorough description of the effect that I found, The National Commission on Marihuana (see Part III) gives the following detailed description: "The closest non-drug approximation may be the altered state of consciousness experienced in the hypnotic trance or transcendental meditation or the, transition zone between waking and sleep (Weil, 1971). ... at low doses (usually smoked dose about five mg. THC) include euphoria, with restlessness and mild mental confusion. Sensory perception of the external environment is altered. Users often perceive an overestimation or slowing of elapsed time.... Visual alterations reported are more vivid imagery and seeing forms and patterns in objects that are usually amorphous. Increased awareness of subtle qualities of sound such as purity, distinctness or rhythm are characteristically perceived by users. A dreamy, relaxed state and disinhibition, with uncontrollable laughter is reported and users often believe that interpersonal relations are altered, and act to potentiate social interaction. At moderate doses intensifications of changes experienced are reported. Users' reports include disturbed associations, dulling of attention, vivid visual imagery, fixed ideas, rapidly changing positive and negative emotions, fragmentation of thought, flight of ideas, impaired immediate memory, altered sense of identity, increased suggestibility and a feeling of enhanced insight. At higher doses, interpersonal relations are dulled and the user feels less social and more withdrawn. At larger doses psychotomimetic (hallucinogenic-like) phenomena are experienced in a wavelike fashion. These include distortion of body image, depersonalization, visual illusions and distortions, synesthesia, dream-like fantasies and vivid hallucinations."

    In conclusion, the gap between the way scientists describe the effect of THC and the way users describe it is a matter of purpose, and a matter of definitions. In modern papers, the description of a "high" is expected to be understood by readers, so it never makes it into the description of THC effects. Rather, the effects are stated in medical terms only, based on psychiatric definitions. Thus, it isn't a "high". It's a "psychotic event". And "psychotic" seems to have a floating definition in some cases (as might "anxiety", which is, interestingly, described often by scientists but rarely mentioned in the user descriptions).  The relative prevalence of bad things happening while on cannabis for short-term users is somewhere between 10-20%, perhaps higher for women then men. Now that the risk has been quantified and defined, Jimmy and Freddy can now make more informed decisions. Way to go, guys!


    III. Commissions and Official Stances


    Below are direct quotes on marijuana policy by authoritative agencies.  in case you don't want to read them, here's a summary: All federal government agencies are strongly opposed to legalization, but recognize that there are chemicals in it that could have medical application and recommend that these chemicals be studied under tightly controlled conditions. Official reports suggest that it be decriminalized and administered by doctors. All the statements discourage its recreational use and discourage its non-supervised medical use by individuals.

    Office of National Drug Control Policy (via Whitehouse.gov 2012): "Marijuana and other illicit drugs are addictive and unsafe especially for use by young people.  As officials with the National Institute on Drug Abuse state, drug addiction is a progressive disease and the earlier one starts, the more likely are the chances of developing a substance use disorder...Although, some of the individual, orally-administered components of the cannabis plant ... have medical value, smoking marijuana is an inefficient and harmful method for delivering the constituent elements that have or may have medicinal value... To date, the FDA has not found smoked marijuana to be either safe or effective medicine for any condition...Furthermore, the Administration opposes drug legalization.  Legalization  threatens public health by increasing availability of drugs and undermining prevention activities. It also hinders recovery efforts and poses a significant health and safety risk to all Americans, especially our youth. Marijuana is a harmful drug and its use should be prevented and treated – not promoted."

    National Institute of Drug Abuse (letter by Nora Volkow 2012)The use of marijuana can produce adverse physical, mental, emotional, and behavioral effects. It can impair short-term memory and judgment and distort perception. Because marijuana affects brain systems that are still maturing through young adulthood, its use by teens may have a negative effect on their development. And contrary to popular belief, it can be addictive.  We hope that this Research Report will help make readers aware of our current knowledge of marijuana abuse and its harmful effects.


    Federal Drug Administration (given in 2006, updated in 2009): "...continues to support that placement and FDA concurred because marijuana met the three criteria for placement in Schedule I under 21 U.S.C. 812(b)(1) (e.g., marijuana has a high potential for abuse, has no currently accepted medical use in treatment in the United States, and has a lack of accepted safety for use under medical supervision). Furthermore, there is currently sound evidence that smoked marijuana is harmful. A past evaluation by several Department of Health and Human Services (HHS) agencies, including the Food and Drug Administration (FDA), Substance Abuse and Mental Health Services Administration (SAMHSA) and National Institute for Drug Abuse (NIDA), concluded that no sound scientific studies supported medical use of marijuana for treatment in the United States, and no animal or human data supported the safety or efficacy of marijuana for general medical use. There are alternative FDA-approved medications in existence for treatment of many of the proposed uses of smoked marijuana."


    American Medical Association (from 2009 report): Results of short term controlled trials indicate that smoked cannabis reduces neuropathic pain, improves appetite and caloric intake especially in patients with reduced muscle mass, and may relieve spasticity and pain in patients with multiple sclerosis.  However, the patchwork of state-based systems that have been established for “medical marijuana” is woefully inadequate in establishing even rudimentary safeguards that normally would be applied to the appropriate clinical use of psychoactive substances.  The future of cannabinoid-based medicine lies in the rapidly evolving field of botanical drug substance development, as well as the design of molecules that target various aspects of the endocannabinoid system.  To the extent that rescheduling marijuana out of Schedule I will benefit this effort, such a move can be supported.

    The Report on the National Commission on Marihuana and Drug Abuse,1972: (From medical policy statement) Looking only at the effects on the individual, there, is little proven danger of physical or psychological harm from the experimental or intermittent use of the natural preparations of cannabis, including the resinous mixtures commonly used in this country. The risk of harm lies instead in the heavy, long-term use of the drug, particularly of the most potent preparations.The experimenter and the intermittent users develop little or no psychological dependence on the drug. No organ injury is demonstrable.Some moderate users evidence a degree of psychological dependence which increases in intensity with prolonged duration of use. Behavioral effects are lesser in stable personalities but greater in those with emotional instability. Prolonged duration of use does increase the probability of some behavioral and organic consequences including the possible shift to a heavy use pattern.The heavy user shows strong psychological dependence on marihuana ... Organ injury, especially diminuation of pulmonary function, is possible. Specific behavioral changes are detectable. All of these effects are more apparent with long-term and very long-term heavy use than with short-term heavy use. (From "Other Recommendations"Recommends that the voluntary sector be encouraged to take an active role in support of our recommended policy of discouraging the use of marihuana.  (From Final Comments:) Considering the range of social concerns in contemporary America, marihuana does not, in our considered judgment, rank very high. We would deemphasize marihuana as a problem.


    The National Academies Study: Marijuana and Medicine 1999. It's so long that you should probably  Read it yourself. Basically it sees potential in marijuana in medicine and recommends dropping to Schedule 2 level, and cites restrictions on marijuana as a barrier to its development as a legitimate medical drug. Here's a snippet from page 126: "Marijuana is not a completely benign substance. It is a powerful drug with a variety of effects. However, except for the harm associated with smoking, the adverse effects of marijuana use are within the range tolerated for other medications. Thus, the safety issues associated with marijuana do not preclude some medical uses...Three factors influence the safety of marijuana or cannabinoid drugs for medical use: the delivery system, the use of plant material, and the side effects of cannabinoid drugs. (1) Smoking marijuana is clearly harmful, especially in people with chronic conditions, and is not an ideal drug delivery system. (2) Plants are of uncertain composition, which renders their effects equally uncertain, so they constitute an undesirable medication. (3) The side effects of cannabinoid drugs are within the acceptable risks associated with approved medications. Indeed, some of the side effects, such as anxiety reduction and sedation, might be desirable for some patients. As with many medications, there are people for whom they would probably be contraindicated."











    Comments

    Hey David!

    Just wanted to let you know (for what its worth) I can't help but respect both your articles regarding the (questioning with logic) approach you've used while writing about cannabis use. I'm a HUGE Advocate for any cannabis use, since I know (first hand) what prescription abuse can lead to and does lead to. For me, the answer is simple...NO DEATH ASSOCIATED with CANNABIS Use ALONE. I CAN'T SAY THE SAME ABOUT PHARMA, ALCOHOL, and TOBACCO! I teach my children the importance of knowing exactly what each and every drug will do to them (good & bad), while not using the "fear factor" that was used on me. No One taught me that the largest "dealers" wear white coats if a person is not careful and educated on the effects pill popping can cause... I know some people are scared that cannabis use can be a "gateway", but in their defense, that's the only thing they've been told. Please continue to research and find 'truths" about cannabis use and spread it like wildfire! "Knowledge" is Power when it Speaks the Truth, and "Wisdom" Listens. Thank you again.

    Renaisauce
    Angie.
    I appreciate your respect. Thank you.
    Those first two quotes- yikes! big thumbs down:(
    The ONDCP and NIDA are corrupt organizations run by outright liars. Just look at the bizarre crock of bs they are doling out here! The first sentence is so vague it is meaningless. Nora Volkow is unabashadly biased. She considers all cannabis use to be abuse, even an experimenter's first time. The NIDA website for teens is atrocious, filled with made-up scare stories. It makes pot out to be worse than meth.

    My recommendations were to read the reports of the specially-appointed commissions, not the recent, corrupt government agencies. Looks like you may do so in part III? When you read the Indian Hemp Drugs Commission Report (1894), The Laguardia Committee Report (1944), The Commission on Marijuana and drug abuse (1972), and then one or two modern examples - there was a pretty thorough review done in the UK in 2006 I think, and anyway you have been reading up on recent research. What you will notice is that all the same issues, down to the smallest detail have been discussed and examined from the beginning time and time again. Is it dangerous, are users dangerous, does it cause psychosis, what are the long term health effects, what about lowered motivation, or cost to society? When you read the results and responses in these reports, even from 100+ years ago, you see that there really isn't anything new coming out of NIDA/NIH studies, except better understanding of the mechanisms of course. What's especially interesting about the Indian hemp and LaGuardia reports is that they were written in times where use was or had recently been legal and was more accepted. They cover large populations also and are thoughtfully written. The 1972 report has some nice descriptions of effects, though I didn't see the psychosis part you quote above. That must be from a different report, or different version?

    Anyway, stay away from the NIDA :)

    Gerhard Adam
    Bear in mind David, this isn't about logic or science.  This is about the law.  If marijuana were legal, you wouldn't be writing these articles, nor would you be engaged in this research unless you felt compelled to try it yourself.
    Mundus vult decipi
    Renaisauce
    I don't think that's true. I mean, I agree that the reason I'm writing these articles is because they are sociopolitically relevant and prescient, and I want to make sure my opinions are on solid ground.  But even if cannabis were universally legal, there would still be the question of whether or not its a good idea to try it. The need for information on the pros and cons of cannabis use are never going away, as the concerns haven't gone away with lots of legal substances. Antidepressants are legal, but no one would question my motives if I wanted to do the exact same literature search to see if they were good to take. In fact, I might do that down the line. Following the data is the right way to get informed enough to make a decision independent of legality or common opinion. The data knows. Ball don't lie.

    I'm a 32-year-old man who grew up in northeastern public schools where pot was, I've had drug education since I was five, I've consumed media of all kinds, I have a PhD in neuroscience and think about the brain professionally. But in about 6 hours of searching I learned about 50 things about cannabis and the brain that I didn't know, and which have reformed my opinions on this topic significantly. It's made remember how many facts I don't know. And this kind of searching is precisely what we should be doing all the time.

    Gerhard Adam
    I have to disagree, because I expect that when it's all said and done, you aren't likely to write a single article about the pros and cons of alcohol, nor of cigarettes, nor of coffee, etc.

    The reason being that no one would care, and I suspect neither would you.
    Mundus vult decipi
    Renaisauce
    I see your point, and I'll restate it to make sure I see it. The three things you mentioned (alcohol, cigarettes and coffee, and I could add corn syrup and lard,) are all legal substances that have been strongly intertwined with our (Western) culture. All of them have health effects, many of them negative and dose-dependent, but people who use them are aware of the risks and simply don't care. The reasons why they don't care are personal. (Anyone who has never had the opportunity to tell a smoker that they shouldn't smoke should seek out the opportunity. It's loads of fun.) So further articles about their effects are perceived as white noise, because their health effects are considered irrelevant or relatively insignificant to the reasons why people continue to use them. If cannabis was legalized for recreational use in the U.S., it is likely that they would fall into the same category.

    So, then, I open this question to discussion. Once cannabis legalized, do continuing investigations into its effects on health become publicly irrelevant? Let's say that it becomes legal, and then then the recently-made links between cannabis and immune suppression or testes tumors are substantially verified. Would that matter to anyone anymore? Or would those just become more ignored Surgeon General warnings on Camel marijuana cartons? And if they're irrelevant, is that a problem in our culture?



    Gerhard Adam
    I don't see it as a cultural problem.  Instead, what is currently occurring is a conflict between culture and society.  The culture believes that marijuana is fundamentally harmless and an appropriate recreational drug.  Society still maintains that it should have the authority to criminalize it.

    That's where the problem lies, in defining how much authority society should have to intrude on an individual's life in order to keep them safe and/or healthy.

    I say, it's really none of their business, in making the decision. 
    Mundus vult decipi
    Renaisauce
    Wait a minute. What was untrue in Volkow's statement?
    "The use of marijuana can produce adverse physical, mental, emotional, and behavioral effects."



    That's not an untrue, although it is rather broad description and open for interpretation, and is probably more true long term than short term.


    "It can impair short-term memory and judgment and distort perception."


    Everything I've read agrees with that. Distorted perception is the primary affect of THC, and the memory system is a primary brain target. Memory deficits are well-documented, though it isn't all types of memory.  I think working memory takes the real hit.


    "Because marijuana affects brain systems that are still maturing through young adulthood, its use by teens may have a negative effect on their development."


    I don't know about that one. Teen brains are still developing, but I'm don't recall reading an article that shows that teens who smoke cannabis show brain changes compared to those that don't. I may have to dig on that one.


    "And contrary to popular belief, it can be addictive." 


    Now that one is interesting. The number 9% gets bandied about A LOT in statements, but I've looked and looked and I can't find the paper where that number comes from. No one ever cites it, and I disapprove. Further thinking on this seems to get really fuzzy when it comes to the terms "abuse", "dependence", "disorder" and "withdrawl". So I'll be a willing skeptic on that statement. 


    But I think everything else she said is technically correct. Do you have any other criticisms?
    MikeCrow
    Wait a minute. What was untrue in Volkow's statement?

    Maybe it's not "untrue", but it's not in perspective, the same can be said for caffeine, alcohol, nicotine, most prescription medicines, chocolate. If you were to rank caffeine and nicotine at say 3 and 5 respectively, and alcohol at a 10, cannabis should be ranked at about a 7.

    While there are some effects to memory, I suspect it's at least an equal amount dependent on the subject. The same with teen brains, if you take someone who isn't going to put any effort into school, and they're stoned all the time, chances are they're not going to put any more effort into school. If you do not exercise your brain, stoned or not, it will go "soft".

    My personal experience with addiction, is that I'd rather smoke than not, it becomes a habit (in the repetitive activity sense), but other than breaking out of a pleasant repetitive activity, I've not had any issue stopping when I want to stop, with no negative side effects.

    I base this on personal experience, as well as the people I've known. IMO the negatives are more associated to the individual, than their use of cannabis.

    It's the same sort of thing on the "Gateway" drug concern, it's illegal, people who sell illegal cannabis, are likely to sell other illegal drugs, you expose people who have a proclivity to being intoxicated to a large selection of intoxicants that are far more addictive than pot, and it can lead to issues.

    IMO, society would be far better treating drug abuse as a medical condition, than a legal one. Most drugs are not expensive, other than because they are illegal. As well as all of the violence that (being illegal) leads to.
    I'll also note that I would not be the least bit surprised that most major traffickers lead the charge on keeping their product illegal, it's more profitable.
    Never is a long time.
    "If you were to rank caffeine and nicotine at say 3 and 5 respectively, and alcohol at a 10, cannabis should be ranked at about a 7."

    huh? worse than nicotine??? There is no evidence for this. Please don't make up numbers.

    MikeCrow
    They are my subjective rankings, if you don't like them, make up your own. I'm not claiming they are science.
    Never is a long time.
    "...and National Institute for Drug Abuse (NIDA), concluded that no sound scientific studies supported medical use of marijuana for treatment in the United States, and no animal or human data supported the safety or efficacy of marijuana for general medical use."

    It is a lie to state that that no studies support the safety of cannabis.

    Also, we know a lie can be composed of technical truths. She is addressing young people on the web site I mentioned! And how can a scientific organization be so biased? She literally called the first experiment with pot as "abuse" in another of her letters.

    The ONDCP quote (which cites NIDA research) ""Marijuana and other illicit drugs are addictive and unsafe especially for use by young people" reminds me of this testimony from the DEA head Michele Leonhart. These psychos (Nora, Gil the Czar, and Leonhart) just repeat the same talking points like robots:

    http://www.youtube.com/watch?v=ykwaXsQY6Eg

    "Legalization....poses a significant health and safety risk to all Americans, especially our youth"

    How does legalization pose a health and safety risk to ALL Americans?? This is an absurd statement.

    "smoking marijuana is an inefficient and harmful method "

    smoking is an extremely efficient way to control dosage. Many medical users prefer it for this reason. Yes smoking is bad, but so is standing on a busy city street corner and inhaling the fumes. If your neighbor has a wood stove you are probably inhaling more particulates than me. If this is a concern, we should be making delivery safer. This is also why the stronger strains are better. The news always shows people smoking a big spliff loosely held together with reams of thick rolling paper, but most people today are taking small tokes from a pipe-very different.

    UvaE
    David, it's interesting that the term "psychosis" has been used so sloppily by cannabis researchers. The legal issues and war on drugs do distort the science. Meanwhile exaggerated claims about the drug's benefits are also made by users. So we are left to quote Orwell once again: the first casualty of war is the truth.
    Cannabis 'magnifies' internal and external events, experiences, and feelings. It can affect you in a negative or positive way, so it really comes down to the individuals life and how well they know themselves and how far they have come in their own life. Which is why some use it to be creative and others to sit around and be unproductive.

    David Sloan its good that you've brought much needed attention to the Cannabis subject.
    Mi Cro made some very interesting insights on the topic.

    "Ignorance breeds fear"

    Here are a few excerpts from the 1972 report (commissioned by Nixon and expected to rubber stamp his new drug war) that I thought were relevant to the discussion so far. There are some interesting points about individual response and incidence and causes of negative reactions.

    http://www.druglibrary.org/schaffer/library/studies/nc/ncmenu.htm

    The National Commission on Marihuana and Drug Abuse

    Marihuana - A Signal of Misunderstanding.

    Chapter II
    marihuana use and its effects

    Subjective Effects

    A description of an individual's feelings and state of consciousness as affected by low doses of marihuana is difficult; the condition is not similar to usual waking states and is the result of a highly individual experience. Perhaps the closest analogies are the experience of day dreaming or the moments just prior to falling asleep. The effect is not constant and a cyclical waxing and waning of the intensity of the intoxication occurs periodically.

    At low, usual "social" doses, the intoxicated individual may experience an increased sense of well-being; initial restlessness and hilarity followed by a dreamy, carefree state of relaxation; alteration of sensory perceptions including expansion of space and time; and a more vivid sense of touch, sight, smell, taste, and sound; a feeling of hunger, especially a craving for sweets; and subtle changes in thought formation and expression. To an unknowing observer, an individual in this state of consciousness would not appear noticeably different from his normal state.

    At higher, moderate doses, these same reactions are intensified but the changes in the individual would still be scarcely noticeable to an observer. The individual may experience rapidly changing emotions, changing sensory imagery, dulling of attention, more altered thought formation and expression such as fragmented thought, flight of ideas, impaired immediate memory, disturbed associations, altered sense of self-identity and, to some, a perceived feeling of enhanced insight.

    At very high doses, psychotomimetic phenomena may be experienced. These, include distortions of body image, loss of personal identity, sensory and mental illusions, fantasies and hallucinations.

    Nearly all persons who continue to use marihuana describe these usual effects in largely pleasurable terms. However, others might call some of these same effects unpleasant or undesirable.

    As discussed earlier, a wide range of extra-drug factors also influences marihuana's effects. The more the individual uses marihuana and the longer he has been using it, the more likely the experiences will be predominantly pleasurable, and the less likely the effects will be unpleasant. An increasing sensitization to those effects viewed as pleasant occurs as the user has more experience with the drug.

    Persons subject to unpleasant reactions may eliminate themselves from the using group although the occasional experience of an unpleasant effect does not always discourage use.

    Mental Function

    Marihuana, like other psychoactive substances, predominantly affects mental processes and responses (cognitive tasks) and thus the motor responses directed by mental processes (psychomotor tasks). Generally, the degree of impairment of cognitive and psychomotor performance is dose-related, with minimal effect at low doses. The impairment varies during the period of intoxication, with the maximal effect at the peak intoxication. Performance of simple or familiar tasks is at most minimally impaired, while poor performance is demonstrated on complex, unfamiliar tasks. Experienced marihuana users commonly demonstrate significantly less decrement in performance than drug-naive, individuals.

    The greater his past marihuana experience, the better the intoxicated individual is able to compensate for drug effect on ordinary performance at usual doses. Furthermore, marked individual variation in performance is noted when all else is held constant. The effect of marihuana on cognitive and psychomotor performance is therefore highly individualized and not easily predictable. Effects on emotional reactions and on volition are equally variable and are difficult to measure under laboratory conditions, but can be significant.

    The Intoxicated State

    Studies of intoxicated persons have suggested possible explanations for the subtle effects on mental processes produced by marihuana, Generally, a temporary episodic impairment of short-term memory occurs. These memory voids may be filled with thoughts and perceptions extraneous to organized -mental processes. Past and future may become obscured -as the individual focuses on filling the present momentary memory lapse. His sense of self -identity may seem altered if he cannot place himself in his usual time frame.

    This altered state of mind may be regarded by the individual as pleasant or unpleasant. The important factors of dosage and set and setting play a most important role in this determination. When the nature of the drug-taking situation and the characteristics of the individual are optimal. the user is apt to describe his experience as one of relaxation, sensitivity, friendliness, carefreeness, thoughtfulness, happiness, peacefulness, and fun. For most marihuana users who continue to use the drug, the experience is overwhelmingly pleasurable.

    Unpleasant Reactions

    However, when these circumstances are not optimal, the experience may be unpleasant and an undesirable reaction to the marihuana intoxication occurs. In these instances, anxiety, depression, fatigue or cognitive loss are experienced as a generalized feeling of ill-being and discomfort. A heavy sluggish feeling, mentally and physically, is common in inexperienced marihuana smokers who overshoot the desired high or in persons who might orally ingest too large a dose. Dizziness, nausea, incoordination, and palpitations often accompany the "too stoned" feeling.

    Anxiety States

    "Novice anxiety reactions" or feelings of panic account for a majority of unpleasant reactions to marihuana. When the distortion of self image and time is recognized by the individual as drug-induced and temporary, the experience is viewed as pleasurable. Anxiety -and panic result when these changes cause the individual to fear that the loss of his identity and self-control may not end, and that he is dying or "losing his mind." These anxiety and panic reactions are transient and usually disappear over a few hours as the drug's effects wear off, or more quickly with gentle friendly reassurance.

    The large majority of these, anxiety reactions occur in individuals who are experimenting with marihuana. Most often these individuals have an intense underlying anxiety surrounding marihuana use, such as fears of arrest, disruption of family and occupational relations, and possible bodily or mental harm. Often they are older and have relatively rigid personalities with less desire for new and different experiences.

    The incidence of these anxiety reactions may have decreased as marihuana use has become acceptable to wider populations, as the fears of its effects have lessened and as users have developed experience in management of these reactions.

    Psychosis

    Rare cases of full-blown psychotic episodes have been precipitated by marihuana. Generally, the individuals had previous mental disorders or had poorly developed personalities and were marginally adjusted to their life situation. Often the episode occurred at times of excessive stress. These episodes are characteristically temporary. Psychotherapy and sometimes medications are useful in prompt control and treatment of this psychological reaction. In addition, rare nonspecific toxic psychoses have occurred after extremely high doses. This state of nonspecific drug intoxication or acute brain syndrome is self-limited and clears spontaneously as the drug is eliminated from the body.

    Conclusions

    In summary, the immediate effect of marihuana on normal mental processes is a subtle alteration in state of consciousness probably related to a change in short-term memory, mood, emotion and volition. This effect on the mind produces a varying influence on cognitive and psychomotor task performance which is highly individualized, as well as related to dosage, time, complexity of the task and experience of the user. The effect on personal, social and vocational functions is difficult to predict. In most instances, the marihuana intoxication is pleasurable. In rare cases, the experience may lead to unpleasant anxiety and panic, and in a predisposed few, to psychosis.

    Renaisauce
    Isabel,

    The work cited in the 1972 report is interesting, but based on my cursory read of the charts on PubMed, less than half of the currently available data from research on Cannabis was available before 1972, and as I pointed out, work on it really picked up in the last 15 years. The far more recent study my the American Academies study I cited is a much better source of information. 


    (You also pointed out the study from the 1800's, but I'll be honest, I don't trust any health evaluation on anything from the 1800s-- when chewing tobacco, lead paint, cocaine, etc. were all considered fine and useful-- to be very authoritative). 

    But I would be interested on your take on the following question. Take these two facts together,both of which I cited in part I: (1) forensic data on cannabis in circulation around 2004-2005 showed that the plant was being selectively bred and processed to increase the concentration of THC and lower the concentration of the antipsychotic cannabidiol, and that the increase was recent. (2) When bad effects of cannabis are discussed (anxiety, panic attacks or panic syndrome, health effects on lungs, etc), it is usually with the following caveat: "these effects are related to heavy, prolonged use or high-concentration dosage". My understanding is that recreational use is justified as relatively safe based on the assumption that "recreational" doesn't mean "heavy, prolonged use or high dosage".

    So with those two facts together, it seems that using cannabis over a period of years in 2012 is riskier than it was in 1972, since the concentration of THC has gone up, and will likely continue to go up to provide a stronger experience?

    Let me put it another way: should pure delta-9 THC be considered a safe--and legal-- drug?







    All stronger pot means is you smoke less. It is a good thing. However selective breeding may be questionable. As far as the 1972, this was a response to your curiosity about the effects and your observation that the newer reports only talk about negative effects. I think everything about the panic attacks in new users and why they occur, and many other aspects are absolutely valid today.

    I am pretty familiar with the latest research, but I couldn't summarize any *truly* new findings, can you?

    The other reason for reading the early reports, which perhaps I did not make clear, is that they are more honest and straightforward and they look at the whole picture in places and times that were not so steeped in fear and desire for police state control of the populace. I wouldn't use the 1894 report for health information, no. Think of it field studies of an animal or plant that is now extinct in the wild and only lives and reproduces in zoos and laboratories. The new studies use all the modern methods and go into great detail about the physiology of the organism. So do you throw out the "old-fashioned" field studies? Can you learn everything important about the organism from the new studies? Humans and the cannabis plant have a long complex natural history; treating the plant as a strange and scary new concoction threatening society is a weird distortion in itself. As the sections of the 1972 report I quoted point out the effects of cannabis are strongly situational (many other commenters have mentioned that also). Part of "the situation" is the cultural and political environment.

    "Let me put it another way: should pure delta-9 THC be considered a safe--and legal-- drug?
    "

    Isn't that what Marinol is?? But breeding out the other compounds may not be ideal, and is controversial. But I am not an expert there.

    Renaisauce
    Yes, Marinol is THC in a capsule. But Marinol is still a Schedule III compound and is tightly controlled, primarily given in low doses to AIDS and cancer patients (though that might expand). So is there significant movement to make it an over-the-counter compound? Why would you want to have all the messy things associated with smoking (the smell, the smoke itself, the effect on the lungs, etc.) when you could get the same high in an easy to swallow gel capsule?

    And by the way, this should have come up way earlier in the discussion, because studies on the effects of Marinol are very relevant here. If I had more time, this would be Part III.  The FDA description of the drug is very informative and opens up a whole new line of inquiry.
    "Why would you want to have all the messy things associated with smoking (the smell, the smoke itself, the effect on the lungs, etc.) when you could get the same high in an easy to swallow gel capsule?
    "
    One reason would be to have much better control of dosage. While the pills can be made more consistent in composition than the plant (though I would suspect that plants are pretty consistent nowadays, and can themselves be tested) they require a one time oral dose with a delayed effect. Remember, we all keep agreeing that we don't want to overshoot the desired effect, and the effects are situational. If pain relief action of cannabis is "subjective" than is it also "situational" like intoxication is? A delivery method where the patient or other user (like "marijuana" I can't bring myself to use the term "recreational") can control the amount by gradually taking in small, accumulating doses that each have an immediate effect is ideal. One where a preset amount is delivered in one go and has a delayed effect is not ideal for everyone- this is a reason some people don't like brownies.

    Renaisauce
    Isabel,
    (1)

    --" If pain relief action of cannabis is "subjective" than is it also "situational" like intoxication is? A delivery method where the patient or other user (like "marijuana" I can't bring myself to use the term "recreational") can control the amount by gradually taking in small, accumulating doses that each have an immediate effect is ideal"--



    But intoxication is legal, and you can easily buy enough alcohol to kill yourself. If THC can't kill you directly, (although according to the FDA sheet on Marinol, there is a theoretical limit where it can kill you, but it's very high), then why not have the same limitlessness with THC? There's a desired effect of alcohol that is unhealthy to pass, but people cross it all the time and its totally socially accepted. And you yourself said that higher concentrations actually means less overall volume/duration usage. If alcohol is the model for the argument of legalization, is it not also the model for the argument for widespread availability at doses of your choice? 

    (2) 

    That said, we do agree that there is such a thing as an "unhealthy limit" to how much THC one should accept in the blood stream. So let's say that cannabis is universally legalized across the country.  What laws would have to be in place so that the processing of the product itself doesn't exceed that limit (for example, the kind of processing that raises THC concentration from the 5-15% to 40%)? Would there need to be a law that cannabis can't be processed or sold so that it has a THC concentration above X, or an equivalence above that of the strongest Marinol (10 mg)? And would that law be as enforceable as anti-marijuana laws are now? Should legal cannabis growers have a licence and have their product inspected by the USDA, and therefore should non-licensed cannabis be illegal?  Sorry, that turned into four questions.


    "If alcohol is the model for the argument of legalization, is it not also the model for the argument for widespread availability at doses of your choice? "

    You really can't make the comparison, because with pot, less is more. Smoking more will not get you much higher, it will just push you past your comfort zone (too high, paranoid, anxious) or will make you sleepy and your brain foggy. For most people these are unpleasant states which is what is meant about not wanting to overshoot the desired effect. This is hard to control with a brownie or a pill. Even regular smoking decreases the effect, so ideally a pot smoker would take a few days off frequently and smoke only to a certain point. But even us experienced users forget this all the time! But generally I don't want pot that is advertised as strong- it's too hard to control dosage. I also feel like I don't get the same high from hash or hash oil.

    "That said, we do agree that there is such a thing as an "unhealthy limit" to how much THC one should accept in the blood stream. So let's say that cannabis is universally legalized across the country. What laws would have to be in place so that the processing of the product itself doesn't exceed that limit (for example, the kind of processing that raises THC concentration from the 5-15% to 40%)?"

    Again, it is not so much a matter of health as one of desired effect by the user. The amount of THC that makes a user too high or tired and sleepy is many orders of magnitude lower than what might be considered actually dangerous, so again, there is no comparison to alcohol. An ounce of pot could get an adult high at least 200 times but your toddler could eat the who lot in one sitting and will not be permanently adversely affected. Some users might want processed product like hash or oils so they can add it to other things, so why not?

    " Should legal cannabis growers have a licence and have their product inspected by the USDA, and therefore should non-licensed cannabis be illegal? "

    Sure, large commercial growers should be treated as all agricultural producers, why not? People should know what they are buying. But as with wine now, I think we should allow boutique production and also home growing of small amounts.

    To quote the DEA's own administrative law judge, the late Francis Young, "cannabis is one of the safest therapeutic substances known to man." From his 1988 report... add the fact of the virtual impossibility of a fatal overdose (even water can't claim that) to the equation and one might get the feeling someone's having their leg pulled.

    Mr Sloan must also realize he speaks as one of the 3 blind men describing an elephant. As do all the others looking for the negative side of cannabis when they don't and/or haven't personally explored/experienced the topic.

    Personally, my observations as a 4 decade cannabis consumer tells me that those who vehemently oppose cannabis are nuttier than those who consume. And obviously not everyone should smoke pot. But for those who don't consume to assume to describe to me the effects of cannabis consumption is perilously close to absurd.

    Nowhere in the growth, harvest or consumption of cannabis does criminal activity occur. Seeds are planted, plants are grown, harvested and consumed. Where is the crime? The crime is a made-up phantom fantasy of that arch-enemy of freedom, Harry Anslinger. And that too is perilously close to absurd.

    Now, should I point out that a government study conducted by the NIH in Virginia actually first found cannabis is an effective anti-cancer agent, I also must point out that the study was buried where it gathered dust for 25 years. Of course that means I also must point out that NIDA's entire mission is to find harms, not truth and that the ONDCP's mission clearly directs them to ignore, deny and obfuscate away from discussing the issue of legalization.

    See, the part that gets my goat is this anti-cannabis campaign has for decades destroyed more in this country than the most noxious reactions from using cannabis. We're examining urine with a microscope to detect pot use? Why? If it's such a problem one must ask, where are all the bodies? With possibly 1/3 of our nation now having at one time in their life at least tried cannabis and a minimum of 1 in 10 folks at least occasional consumers, by golly there otter be mayhem everywhere.

    And while there are cannabis proponents that indulge in hyperbole much of what anyone with a day or two of reading can discover will come to find out that all along it's been a lie. Quibbling over details doesn't make it less a lie. While the wonks quibble, folks are arrested, SWAT breaks down doors (and maybe shoots the family dog), jobs are lost are not gotten... all for a lie. A lie both racist in origin and in practice.

    And to be honest... this is no longer about cannabis David, it's about Prohibition. And the failures of Prohibition exponentially outweigh any and all of the harms of cannabis. That's fact.

    Discover Law Enforcement Against Prohibition. Read up on Tod Mikuriya, the Compassionate Investigational New Drug Program, read judge Young's report (and Cliff Schaffer's Drug Library has all those studies, La Guardia etc). All research on the positive effects of pot occurs outside the US. Also read up on doctor Melamede, Israel's work, and Manuel Guzman in Spain. The list goes on but if you're seeking the truth you have to get away from the government sites.

    And for the best broad overview, the late Jack Herer's the Emperor Wears No Clothes is indispensable. Oh... and watch Reefer Madness keeping in mind the film makers were serious. You can wear out a clutch plate on that one alone.

    Explained Perfectly.

    Renaisauce
    Allan,

    Two responses:

    1) You have to be really careful with "it causes/prevents" cancer studies. You have to look at the details. Since I have not seen that article you cite (could you cite it?) I can't judge it. (specifically, I'd want to know exactly which chemical in a cannabis plant has anticarcinogenic effects, and if it is a chemical that is prevalent in the plant). But I suspect that there are as many articles linking cannabis to some form of cancer (as I cited in Part 1) as those that claim an anticarcinogenic effect. I'm not saying it causes cancer. I'm saying that there are many things which simultaneously do and do not cause cancer and you have to be really specific on your claims.

    2) The other side to the Prohibition argument is this (and Gerhard surely has something to say on this): should every consumable product be made legal? That eliminates all the bloody conflict and organized crime, doesn't it? And it places the burden of education on every substance on the individual. I pose this as an honest question in this w: on what basis should any consumable substance be made illegal, and what is the specific role of health science in that basis?
    MikeCrow
    To your second question, while I don't expect it to happen, and I do expect to be called nuts, I think the only sane answer is yes.

    It will cause bad things to happen, but IMO we are already causing worse things to happen with prohibition. We can look at the history of alcohol for reference.
    Never is a long time.
    Gerhard Adam
    ...should every consumable product be made legal?
    That is the difficult question, isn't it?  While we can readily discuss marijuana, the problem becomes a bit dicier when we consider substances like heroin.  Even if we argue that even this should be legalized, then why not prescription drugs?  Why have prescriptions at all?

    Again, I think we can look to thinks like alcohol, cigarettes, caffeine, etc. for some guidance.  In the case of caffeine, there is no societal consequence beyond and individual possibly being more excitable, so there's no much to be done here.  In the case of cigarettes, there is increased public awareness, and some smoking bans to curtail usage in inappropriate venues.  Alcohol has the additional restrictions against engaging in activities, etc.  Each has different social consequences that must be addressed beyond simply that they are legal.

    Similarly, marijuana falls into a category similar to alcohol.  I assume that many other substances would be similarly classified.

    In the case of the opiates, we have a different problem.  While legality would curb the criminal aspect of it, the cost to society becomes considerably higher in terms of managing restrictions, as well as having to afford treatments to individuals if they elect to stop using.  In short, these are drugs that are not strictly individual choice, because of their destructive addiction properties.  Certainly cigarettes, etc. are addictive, but breaking those addictions are still within the purview of individuals if they choose to do something about it.  It may be difficult, but it's not on par with heroin in terms of social consequences nor quitting.

    Prescription drugs are also in a different category, because of their association with medicine, in that there is an expectation of safety in their use, so restricting access is well within the scope of the producers. 

    Certainly arguments can be made countering these points, but we also have to consider whether even the worst drugs aren't better handled by increased public education [again, consider alcohol and cigarettes] versus legal restrictions.  In the case of the law, everyone loses, because society incurs the cost anyway, while the individual's life is generally destroyed by prison.

    So, at the very least it seems that we should decriminalize all these substances.  Of course, the problem society faces, is whether legalizing something is akin to endorsing it.  I think we can see that this doesn't necessarily follow, by considering our examples of alcohol and cigarettes.

    In the end, even with the cautions mentioned above, I don't see any sensible vehicle fo keeping these substances illegal.   I don't really accept the argument that legalization will automatically translate into increased  usage.  Just like having alcohol and cigarettes legalized doesn't compel people to use these products.  Will there be problems?  In my view that's irrelevant, since we already have the problems.  Now, it's only a matter of whether society wishes to keep the problem in perspective or continue to exacerbate it.
    Mundus vult decipi
    Gosh, credit David with being a polite and respectful host. Kudos senor. Those of us on this side are used to encountering the poopflingers for whom the drug war is a righteous and noble jihad.

    Re cancer... start at the 1974 cancer study story:

    http://www.mapinc.org/drugnews/v01/n572/a11.html?310095

    Follow that up with Dr Ethan Russo's work with the 4 patients remaining in the CIND program and his research into cannabis. Also I recommend looking at Rahael Mechoulam's work in Israel:

    http://www.mayoclinicproceedings.org/article/S0025-6196(11)00027-9/fulltext

    If you go here:

    http://beyondchronic.com/2012/08/granny-storm-crow-mmj-reference-list-ju...

    there is a hyperlink to Granny Storm Crow’s MMJ Reference List for July 2012 pdf, perhaps the largest collection of medical cannabis studies out there.

    I'm not a science guy. I'm an educated blue collar 60+ year old single dad that has experienced first hand (and followed extensively for the last decade and a half) the backhand slap of the authoritarian war on drugs.

    Other reading:

    http://drugwarfacts.org/cms/?q=node/54 (an excellent list, studies cited, a bit outdated but is in the process of being updated)
    http://www.cmcr.ucsd.edu/index.php?option=com_content&view=category&id=4...
    Carl Sagan on pot: http://marijuana-uses.com/mr-x/
    Allen Ginsburg echoing what I said in my previous comment about the unexperienced explaing the experience): http://marijuana-uses.com/the-great-marijuana-hoax-by-allen-ginsberg/

    2) for me this is the real, vital, crux of the biscuit. Your question, should every consumable product be made legal? is a good one.

    My answer is yes. My life, my body, my family, my home, are mine - my home is my castle, my body my temple. As I explained in previous comment, no more crime occurs in the planting, harvesting and consuming cannabis than does for growing blueberries (and I love my blueberries too).

    There are those who say but drugs are evil. Ptooey! Nothing save humanity possesses the capacity for "evil." If you lay out a nice kola of ganja, 3 lines of cocaine and an eighth of psilocybin on the kitchen table they will just sit there, inanimate. Not until a human intervenes in the process.

    400,000 people die a year as a direct result of tobacco use. OMG! if that many people died from the flu we'd call it an epidemic. But profit is a powerful motivator (Mammon) and when we all kind of agreed that we had to do something, we didn't send SWAT teams in, no shots were fired and no arrests made. No, we embarked upon a campaign of truthful education demonstrating the real world harms associated w/ tobacco consumption. And it worked. Tobacco use experienced a dramatic and steady decline. Local govts established smoking laws to control its public consumption.

    If opponents of cannabis wish to point to the harms of cannabis then those harms must be shown on scale to other substances. Kind of like this:

    alcohol - 100,000 deaths annually
    tobacco - 400,000 deaths annually
    cannabis - 0 (?) deaths annually

    Hellooo? Perhaps oversimplified but the point is valid.

    Liberty... freedom... are more than concepts. They are universal constants, as organic as birth and death. But for humans to embrace them they must also accept the responsibility that comes with the reality.

    I'm a vet, my 2 older brothers are vets, my dad fought in the Battle of the Bulge in WWII (and the rest of his life but that is another story) and what we served for and to protect was not this massive, bloated, dictatorial and corrupt megomaniacal government owned and run by the richest of the richest.

    As a kid I remember the dominoes of communism. The graphic red arrows sweeping across Asia and northern Europe. I remember U.S. derision of the Soviets and their Gulag prison system, how bad that was and how great it is to live here in the land of liberty where the bell of freedom rings... and now (to quote former drug kzar Barry McCaffrey) we are the new gulag.

    So yes, legalize all drugs. Criminal human behavior, assault, theft, etc, is true crime. Disobeying bad laws is not, in any sense, a crime.

    David,

    Think of it this way. 20,000 (or whatever the number is) recent studies and hundreds of million users for generations and we still can't say it causes cancer. The US government is desperate for some bad news, but even the bad news that comes out is shaky and is usually contradicted by other studies. Doesn't this tell you something right there? A political workaround is to focus on the supposedly carcinogenic compounds in the smoke. Yet, if this is true why aren't these cancer cases (or increased incidence of mental illness) showing up in the epidemiological studies?? Yes, there are reports, but again it's usually a small effect in heavy users only, and other epidemiological studies don't show it, etc. Right there is indirect evidence of a protective effect!

    Renaisauce
    Again, my point was not to say that it does or does not. My point was that its just as easy to say something protects against cancer as to say that it causes cancer, and that you can't just throw out one claim or another without being able to back it up, which the commenter did after I pointed it out.
    Okay, well of course we shouldn't just make up claims. But then what? Here's a link to the more recent UK review I mentioned earlier. http://www.homeoffice.gov.uk/publications/agencies-public-bodies/acmd1/c...

    They specifically look at the psychosis question, concluding that the new research between 2001 and 2005 (which had raised some alarms) did not significantly change assumed risks, which were very low regarding schizophrenia and both low and reversible in terms of other effects (temporary "psychosis". anxiety, panic attacks). They don't find strong evidence that heavy or long term use is a risk (but may be a risk for depression).

    yes, yes it's only from 2005- that was eons ago in cannabis research time! Well, I've witnessed these discussions and my prediction is that those intervening years have not produced any game-changing revelations.

    I think there is a point being missed here and that has me puzzled.

    Again, I'm just an mid-level college educated white American blue collar male but that the government intentionally hides a study demonstrating effectiveness against cancer borders on either insanity or a grossly misplaced sense of power. When asked "where are the bodies?" from cannabis harms (cancer, psychosis, or personal injury) no one can point them out to me. Tobacco piece of cake, alcohol ditto, cancer ditto... the claim that that for every good there is a harm is a weak approach. The fact of the impossibility of fatal overdose puts cannabis in a category of its own.

    Further... cannabis need not be smoked (which is where the cannabis-cancer connection is argued) and no medical cannabis user I know (and I know many) will recommend that method. Vaporization, tinctures, edibles, teas... all are commonplace in the mmj community (read the NY Times article on Israel I perviously linked to).

    This isn't about molecules, it's about people and their rights and the government and its century long process of criminalizing a once common medicine and farm staple.

    It's about asking why industrial hemp remains illegal when it has no potential for intoxication and no potential for abuse.

    It's about asking why people like Donald Scott, Peter McWilliams, Patrick Dorismond and too many more are the unacknowledged (except by drug war opponents) fatalities not of cannabis but its prohibition.

    The war on drugs is a fraud. The WO(s)D is in reality a war on people. The war on drugs is racist. The war on drugs is anti-American.

    Gerhard Adam
    David

    Part of the problem here is that you're looking for justification.  This is nearly impossible, because for every positive claim someone can level a negative one.

    As an example, consider how you can justify people driving automobiles, where in the U.S. alone, over 30,000+ individuals die every year.  No matter what argument you make, someone else can argue that such a death rate cannot be justified.  This has a clear and undisputed impact on the health and welfare of members in our society, so why do we allow it?
    Mundus vult decipi
    MikeCrow
    This has a clear and undisputed impact on the health and welfare of members in our society, so why do we allow it?

    Because of the value both to individuals and to society. But alas, I predict in 5-10 years the nanny state will mandate autonomous vehicles, just because they love us so much. And while I'll be in line for an affordable autonomous car, there are time when I'll still want to drive it myself.
    Never is a long time.
    I understand the fact that you limited your search to Pub Med and NIDA research. I respectfully submit that the nature of NIDA and of Pub Med organizations both provide you with skewed results (albeit for different reasons). There have been over twenty thousand peer reviewed studies on marijuana done, and virtually no significant side effects can be found. Medicinally here are just a few of the potentially beneficial effects that have/are being researched: http://boards.cannabis.com/medicinal-cannabis-health/161539-granny-storm...
    It has no known adverse drug interactions, zero overdose potential.
    If we're actually doing research to decide if taking a drug is a "good idea" I would venture a guess that no drug, legal or not would fit into the "good idea" category. People don't try drugs because they are a "good idea". It's kind of a silly premise. But okay. I'll accept it. But as a psychologist (retired) I would assert that we need to realize that people experiment with altered states from a very early age, and are going to do so regardless of whether it is a good idea. The current social debate centers(or should center) on whether it is a "good idea" to lock people up in cages for experimenting with pot, since the relative harms to the individual and society (the putative reason we keep it illegal) are so few. Is it really in the interest of society to disallow the legal choice of an arguably safer substance than alcohol?
    I think we can safely say your hypothetical young person SHOULD come away with the conclusion that it is not a "good idea" to try a drug. Any simple cost benefit analysis should conclude that. We need to educate kids on the risks of these substances, but acknowledge that good or bad, many, if not most, will try them anyway.

    David,when you use any "science" quoted from NHS/NIDA or any of the drug war propaganda machine's sources you have left the field of science and entered they're world propaganda.

    With over one half of American's having access to mmj and hundreds of thousands people using it without one reported harm,,,just how safe does a medicine have to be? Plus the medical program that has been going on using government grown marijuana and issued monthly to the remaining participants since the late 70's,,they have all the data necessary to establish marijuana use as a medicine but refuse to do so.

    Meth and cocaine were Shedule 1 drugs at one time but the DEA removed them because clinical trials for them were allowed by NIDA and the DEA. The only clinical study done on smoked marijuana showed positive results for treatment of MS and the ONDCP reported they had issues with the study,,no information has ever been offered on what the issues were.

    That is how the ONDCP and the bureaucratic propaganda machine has operated since it's inception. Even the administrator of NIDA has admitted that NIDA does not do medical research and they have the final say on any studies allowed. All they fund is harm studies,,try getting the total amount of tax dollars spent by NIDA since it's inception on marijuana research from the GAO some time.

    Renaisauce
    I've seen a lot of comments here about the NIH, NIDA, FDA etc, the general gist being about how they are not objective bodies but propaganda machines that are intent on fabricating science to fight both the truth and the will of the people. While I'm fully accepting of the idea that federal agencies can't be completely unbiased because the job security of their leaders depends upon favor with politicians, I feel like I have to defend them a little. The heads of the NIH, NIDA and FDA are, after all, my people.
    The heads of those groups and others in their administrations are smart and rational people. They're more than capable of identifying truth and thinking for themselves. And they've got just as much access to the body of research as we do, maybe moreso. I don't know if you can become a successful scientist without having at least some appreciation for the need to find fact over bias. Of course, scientists are human, but they generally aren't irrational obstructionists. I say, give them a little credit for having their own brains.  You don't have to agree with them, but don't dismiss them as mindless government puppets if they don't agree with you. 

    And for all those people commenting about how federal agencies are only funding cannabis research to find fault with the drug, I think that's disingenuous. There would be no accepted evidence for any effective or safe medical use of THC without A LOT of NIH and FDA investigation. The fact that clinical trials of THC are expanding (to things like Tourettes syndrome)  indicates that the NIH isn't opposed to that work even if it could provide fodder for legalization proponents. 

    I'm aware that there could be a significant and emotional backlash to these comments. Very well. But now I feel that I've defended the honor of my siblings in science.
    First, please, I don't think anyone has suggested "fabrication" - and I don't know of any evidence for this. But lying? Yes, I've provided examples and can provide more. And I understand your skepticism and share your distress; it does seem incredible. But that's not a reason to hide your head in the sand.

    " You don't have to agree with them, but don't dismiss them as mindless government puppets if they don't agree with you. "

    It's not about whether or not they agree with me. It's whether they agree with their own evidence. It's whether they are honest about the science when it comes to communicating with the public, when they are tasked with educating young people (eg the NIDA website for teens). And they are not.

    When Nixon's mostly conservative, hand-picked commission returned with their advice to de-criminalize (and the word is they wanted to advocate for full legalization but were afraid to) their fear was justified - Nixon was outraged, tossed their recommendations in the garbage as he stepped up enforcement, and at least one commission member's career was ruined. z

    Sorry, my last comment was cut off, but anyway

    "The heads of those groups and others in their administrations are smart and rational people. They're more than capable of identifying truth and thinking for themselves."

    They are subject to intense propaganda themselves. I have been involved in a long battle with the popular NIH/NIDA-funded blogger DrugMonkey and am often left incredulous over his lies about my position and my previous comments, his refusal to look at the racism of the drug war, and other strange anomalies (considering that he is otherwise intelligent and a very outspoken anti-racist). He often posts about some obscure study of a rare condition that has been blamed on cannabis (for example "cannabis hypermenesis" where people throw up constantly and are only relieved by hot showers) or perhaps a N=14 study of former smokers that "proves" how addictive pot is but didn't correct for cigarette smoking or other drug history, or whatever, and he starts out by saying "wait til the legaleeze folks see this I wonder how they will respond. Readers like Isabel, who claim marijuana is totally harmless and totes magical..." WTF?! I never make these claims, so I constantly defend myself and yet he says the same thing the next time. Legaleeze it folks? Meanwhile no serious groups fighting for legalization make those claims either. It's bizarre. Who can explain his behavior? One time I looked at the ONDCP website and they were going on about "those legaleeze it folks" - somehow DrugMonkey has picked up this lingo and attitude...it gave me a little insight anyway.

    vongehr
    If you were actually interested, as you claim, into the sociopoliticoblahblah, you would not support the propaganda about that it is all just about the effects on Jimmy, but you would realize the elephant: The war on drugs is the problem!  We do not legalize for Jimmy, we need to legalize drugs or else organized crime and mass incarceration and so on completely destroy society, as they are happily doing right now, because if Jimmy does not give his money to the underground, it does not matter. We WILL give our money, because if society does not allow us to at least get high while having to endure all this shit, we give a shit about society in return!
    " Furthermore, there is currently sound evidence that smoked marijuana is harmful."

    David, if you had made any inquiries to try and verify that (false) statement, you would not only have failed to find anything whatsoever to back it up but would have come across the following peer-reviewed science, done by NIDA themselves:

    Researchers at the Kaiser-Permanente HMO, funded by NIDA, followed 65,000 patients for nearly a decade, comparing cancer rates among non-smokers, tobacco smokers, and marijuana smokers. Tobacco smokers had massively higher rates of lung cancer and other cancers. Marijuana smokers who didn't also use tobacco had no increase in risk of tobacco-related cancers or of cancer risk overall. In fact their rates of lung and most other cancers were slightly lower than non-smokers, though the difference did not reach statistical significance. Sidney, S. et al. Marijuana Use and Cancer Incidence (California, United States). Cancer Causes and Control. Vol. 8. Sept. 1997, p. 722-728.

    Donald Tashkin, a UCLA researcher whose work is funded by NIDA, did a case-control study comparing 1,200 patients with lung, head and neck cancers to a matched group with no cancer. Even the heaviest marijuana smokers had no increased risk of cancer, and had somewhat lower cancer risk than non-smokers (tobacco smokers had a 20-fold increased Lung Cancer risk). Tashkin D. Marijuana Use and Lung Cancer: Results of a Case-Control Study. American Thoracic Society International Conference. May 23, 2006.

    1) Tobacco is cancer causing largely because it delivers specific carcinogens such as NNK and NNAL that are not present in cannabis. Not all "tar" is created equal, and tobacco has some of the most carcinogenic types of tar known to science, whereas cannabis does not.

    http://jnci.oxfordjournals.org/cgi/content/full/91/14/1194

    2) Cannabis (marijuana) use is associated with a DECREASE in several types of cancer... potentially even providing a protective effect against tobacco and alcohol related cancer development.

    So there we have it: Tobacco Causes Cancer and Cannabis Prevents Cancer - even when smoked!

    "Components of cannabis smoke minimize some carcinogenic pathways whereas tobacco smoke enhances some. Both types of smoke contain carcinogens and particulate matter that promotes inflammatory immune responses that may enhance the carcinogenic effects of the smoke. However, cannabis typically down-regulates immunologically-generated free radical production by promoting a Th2 immune cytokine profile. Furthermore, THC inhibits the enzyme necessary to activate some of the carcinogens found in smoke. In contrast, tobacco smoke increases the likelihood of carcinogenesis by overcoming normal cellular checkpoint protective mechanisms through the activity of respiratory epithelial cell nicotine receptors. Cannabinoids receptors have not been reported in respiratory epithelial cells (in skin they prevent cancer), and hence the DNA damage checkpoint mechanism should remain intact after prolonged cannabis exposure. Furthermore, nicotine promotes tumor angiogenesis whereas cannabis inhibits it."

    See:http://www.harmreductionjournal.com/content/2/1/21

    Nice discussion.

    Regarding cannabis and cancer, our best science on the topic, funded by NIDA, suggests not only that cannabis does not cause cancer, but that it may have a protective effect, even when smoked.

    Here is the WaPo's coverage: http://www.washingtonpost.com/wp-dyn/content/article/2006/05/25/AR200605...

    Thanks to David and commentators for this informed thread on one of my botanic hobby in an open, science oriented setting.
    To the risk of steering the topic to more "soft brained" socio-political insights, may I ask your opinions on : why are weed legalization opponents so convinced it's important ?

    I am not aware of any published academia research explaining what it's like to experiment with an attitude of strong opposition to legalization. What are the feelings and the motives of denying others the right to be recreationally high on hemp ? What are the risks associated with this practice (long term) ? Are there benefits/pleasure to be taken in such a choice ? Is it easy to stop believing in the dangers of marijuana for society once you did ? Will you change your lifestyle, orient your relationships and sacrifice your inner self to keep a strong will to eradicate all forms of THC intoxication from the world ?
    I will assume that the opponent to legalization is not himself a consumer (though that might happen). I will also grant him the credit that it is (has become) a true conviction, not just stemming from a convenient political agenda or maintaining a personal status.
    I haven't myself ever tried to ban cannabis, except for myself for a few years, so I can only conjecture, but my take on that is, fear of something, fear of a society with too many people too high too much of the time maybe ? A more dreaming(slouchy?) and less hard-working(realist?) society for sure. A joint is never so good than when it's smoked in a relaxed, carefree context, and the risk is to create the conditions where it is so good... Exacerbation of perception and slight psychosis with detachment makes a good standing point to consider how silly society as a whole (and one personal life) can be, leading to authority/doxa questioning (and possibly personal angst/depression if that's so bad). My feeling is, as less dangerous as cannabis can be (and still it is dangerous) compared to alcohol and tobacco, the later legal drugs are perceived as lesser social perils by those in charge, at least for their idea of what the society should be. Tobacco is quite a good stimulant and helps focus on intellectual tasks or cope with more mundane stressful works for hours and hours a day (the longer the day, the more cigarettes, and reciprocally). Too bad it gives cancer. Alcohol is a necessary evil as everyone (well, most...) need a bit of serious intoxication one and then to release the pressure, avoid petrification, and keep going. Whatever nasty one might say of his job or boss (or parents or children...) while drunk is rarely of effect the next day. Shame that some might end their career (parenthood...) drinking every day.
    I would say this is probably exaggeration (distorted sense of reality?) but cannabis is perceived by prohibitionists as a transformative drug, hence the most dangerous of all. For those in fear of a society of the joint: probably the only possible real regulation, already in place, is self regulation. Not that many people are really wanting to be that high that much time in their lives, a lot are circumscribed to the US west coast, and since weed "dependence" is so limited and easy to break there is no danger that practice goes beyond personal tastes and freewill, as far as leaves are concerned. Diversity is a good thing.