Health - Does cannabis use lead to mental-health problems?: findings from the research

[Lunar Loops]

This note from Australia's parliament does not offer any new evidence either way, but does propose a rather refreshing approach to communicating the subject matter, namely being more truthful:

Research Note no. 21 2006–07

Does cannabis use lead to mental-health problems?: findings from the research

Luke Buckmaster and Matthew Thomas
Social Policy Section
7 June 2007

Introduction

In 1987, a large-scale Swedish study confirmed an association between cannabis use and the development of schizophrenia. Ever since, it has become widely accepted by clinicians that there are links between cannabis use and mental illness.(1) Experts have expressed particular concern about the mental-health effects of cannabis use on young people, as ‘adolescence is the developmental stage when drug-using patterns emerge and teenagers may be more vulnerable than adults to the effects of cannabis’.(2)
However, the research to date suggests that the relationship is complex—for example, there is ongoing debate about causality, as well as over the role of other factors in the development of mental illness among cannabis users.
This Research Note provides an overview of recent research into the links between cannabis use and mental-health problems.

Cannabis use in Australia

Cannabis is the most commonly used illicit drug in Australia. According to the 2004 National Drug Strategy Household Survey, one in three (33.6 per cent, 5.5 million) Australians aged 14 years and older have used cannabis in their lifetime. At the time the Survey was conducted, one in twenty (4.6 per cent, 0.8 million) Australians had used cannabis in the last week.(3) The average age at which Australians first use cannabis is 18.7 years.(4)

Recent research

There is now a significant volume of research which shows an association between cannabis use and mental-health problems. However, according to Professor Ian Hickie, Executive Director of the Brain and Mind Research Institute at the University of Sydney, much of the science in this area is ‘relatively new’.(5)
The two main claims that have been made in the research about cannabis use and mental health are as follows:

• that cannabis use is related to the development of psychotic disorders such as schizophrenia among some cannabis users, and
• that cannabis use is related to the development of depression and other mood disorders among some cannabis users.

The research in each of these areas is discussed below.

Cannabis and psychosis

It is generally accepted that the immediate effects of cannabis use can include mood changes, including feelings of panic, anxiety and mild paranoia. These short-term mood changes are dose-dependent (that is, their severity is usually related to the size of the dose taken), and usually do not persist after the effects of the dose have worn off.(6) Various studies have demonstrated that cannabis use can also be associated with short-term psychotic (or quasi-psychotic) symptoms among vulnerable individuals, such as hearing voices and unwarranted feelings of persecution.(7)
Most of the research in this area, however, has focused on the relationship between cannabis use and the development of psychotic disorders in the long-term. Psychotic disorders are characterized by ‘disordered thought, feeling or perception, as in delusions or hallucinations … and are said to involve loss of contact with reality’.(8) The two major psychoses are schizophrenia and bipolar disorder.
The association between cannabis use and psychotic disorders appears to be well established. However, there is still considerable debate over whether there is a causal relationship between cannabis use and mental-health problems. Part of this debate has been concerned with the role of predisposition in the development of mental-health problems (that is, whether or not cannabis users who develop mental-health problems were predisposed to these problems and may have developed them anyway). The debate has also focused on the importance of confounding factors (such as the use of other drugs).(9)
Within this debate, four main hypotheses have been advanced.

• Cannabis use causes mental health problems (the ‘causal hypothesis’). This hypothesis encompasses two possible scenarios: scenario a) cannabis use may cause a psychotic disorder (a distinct ‘cannabis psychosis’) that would not have occurred in the absence of cannabis use and, scenario b) cannabis use may precipitate schizophrenia or exacerbate its symptoms.(10)
• Cannabis use may exacerbate the symptoms of psychosis.(11)
• Cannabis use is a consequence of mental health problems (the ‘self-medication hypothesis).
• Cannabis use and mental health problems may coincide as a result of common variables (the ‘common cause hypothesis’).(12)

This paper focuses on the first three of these hypotheses, as these posit a more-or-less direct relationship between cannabis use and mental health problems, and have generated relatively clear research findings. The final hypothesis is difficult for researchers to rule out because many variables co-exist for both cannabis users and people with mental health problems.(13)
According to a recent review of the research to date, the evidence is strongest for scenario b in the first of these hypotheses, and for the third hypothesis. (14)
With respect to scenario a in the first hypothesis, the evidence in support of cannabis use causing a specific ‘cannabis psychosis’ is not strong. It is plausible that high doses of cannabis can lead to psychotic symptoms in the short term. However, the evidence for a distinct cannabis condition or syndrome which would not occur other than from heavy cannabis use is less compelling ‘because the clinical symptoms reported by different observers have been so mixed’.(15) It is also notable that alcohol abuse is a stronger predictor of psychotic symptoms than regular cannabis use (by a factor of four).(16)
With respect to scenario b in the first hypothesis, there is consistent evidence to suggest that cannabis use can bring about the onset of a psychotic condition (like schizophrenia) in people who are vulnerable to psychosis (and who may possibly have developed it anyway).(17) For example, a recent study of 2400 young people in Germany found that ‘exposure to cannabis during adolescence and young adulthood increases the risk of psychotic symptoms later in life’. Further, it found that ‘this association is stronger for individuals with predisposition for psychosis and stronger for the more severe psychotic outcomes’.(18) The significance of these results was that the researchers controlled for other variables known to increase the risk of psychosis, as well as for the effect of the use of other drugs including alcohol and tobacco.(19)
Further, there is good evidence that:

• a younger age of initiation to cannabis use may increase the risks of mental-health problems substantially, and
• the greater the amount of cannabis consumed, the more likelihood there is of developing a mental illness in those who are predisposed to doing so.(20)

However, there are still important unresolved questions about the causal direction in the association between cannabis use and onset of psychosis in vulnerable individuals.(21) Rather than cannabis use causally inducing psychosis, there is a hypothesis that such use is an attempt to ‘self-medicate’, and reduce certain symptoms of a psychotic condition which has already developed independently (sometimes known as ‘reverse causality’).(22) The ‘self-medication’ hypothesis is discussed in more detail below.
There is now reasonably clear evidence to support the second hypothesis outlined above: that cannabis use makes worse the symptoms of psychosis in those individuals already affected by such conditions.(23) One explanation for this is that cannabis (through its active component, tetra-hydro-cannabinol, or THC) affects the dopamine system, a key source in the development of psychotic symptoms.(24)

Cannabis and depressive disorders

As is the case with cannabis use and psychotic disorders, the available research suggests that there is an association between cannabis use and mood or affective mental conditions such as depression.(25) For example, a recently published study of Australian teenagers found an association between cannabis use and depression (whether conceptualised as ‘clinical’—that is, medically diagnosed—depression, or as ‘depressed mood’). However, their study did not determine whether cannabis use causes depression or vice versa, or whether in fact both cannabis use and depression could be caused by a common aetiological (disease-causing) factor or factors(26)
Further, a 15-year follow-up study of 1920 adults in the US published in 2001 showed that use of cannabis increased the risk of major depression by a factor of four. Specifically, cannabis use was associated with an increase in suicidal thoughts and anhedonia (an inability to experience pleasure from normally pleasurable activities).(27)
However, while there is strong evidence supporting an association between cannabis use and mood disorders such as depression, there is considerable debate over the issue of causality. In other words, while it is possible that cannabis use triggers or precipitates the onset of depression, it is not clear that cannabis use actually causes depression.(28) Further, some commentators also argue the validity of the ‘self-medication’ hypothesis in relation to cannabis use and depression: that is, that people suffering from depression ‘self-medicate’ with cannabis, and thus that depression precipitates cannabis use, rather than the other way round.

The self-medication hypothesis

A recent review of the evidence to date on cannabis use and mental health found that, while the self-medication hypothesis is ‘superficially compelling’, most research which has specifically examined it suggests that the hypothesis is weak.(29) For example, the study of 2400 young people in Germany (mentioned above) did not support the self-medication hypothesis: the study found that predisposition to psychosis was not a significant predictor of cannabis use.(30) Other studies have also supported these results.(31)
On the other hand, some studies have found that schizophrenic patients ‘report using cannabis because its euphoric effects relieve negative symptoms and depression’.(32) Others have suggested that the relationship between the two factors is probably more complex than is generally suggested.(33) For example, a long-term New Zealand study reported in 2000 that mental-health problems among 15–year-olds were a predictor of cannabis use at 18, while cannabis use at 18 was a predictor of mental-health problems at age 21.(34)
Given the complexity surrounding issues of causality and the persistence of arguments for the validity of the ‘self-medication’ hypothesis, recent reviews have identified the need for further research in this area. Nevertheless, it should be noted that most reviews tend to suggest that the ‘self-medication’ explanation is weaker than arguments for a causal role of cannabis.(35)

Recent national data in Australia

Two recent major national reports or surveys have produced data which supports the argument that cannabis use is associated with mental-health problems.
According to the Australian Institute of Health and Welfare’s (AIHW) Mental health services in Australia 2003–04 report, people who regularly use cannabis are likely to experience higher levels of ‘psychological distress’ (including anxiety and depressive symptoms).(36)
The 2004 National Drug Strategy Household Survey found that cannabis users are twice as likely to report diagnosis and/or treatment for a mental-health condition than non-users. It found that, of recent marijuana/cannabis users, 16.5 per cent reported diagnosis and/or treatment for a mental-health condition in the last 12 months, compared with 8.6 per cent of non-users. (On the other hand, 0.9 per cent of recent cannabis users reported diagnosis and/or treatment for diabetes, compared with 4.4 per cent of those who had not used cannabis in the last 12 months).(37)

Evidence to the contrary?

There is little, if any, available evidence that contradicts the various studies discussed above which show an association between cannabis use and mental-health problems (however the association is characterised).
One study published in the medical journal The Lancet in 2004 argued that the evidence for a causal link was not strong. The study found that confounding factors such as the fact that cannabis users are also more likely to report ‘an increased use of other illicit drugs’ make it difficult to conclusively demonstrate causality between cannabis use and psychological problems.(38)
However, research conducted by a team in New Zealand found that it is unlikely that the link between cannabis use and psychotic symptoms results from confounding factors.(39) This directly challenges the argument advanced by the authors of the Lancet study.
Nonetheless, other researchers have also questioned the link between cannabis use and mental illness, particularly with psychotic disorders such as schizophrenia. For instance, there is an argument that if the association between cannabis use and mental illness were genuine, there should have been an increase in the incidence of schizophrenia in the last three decades as teenage cannabis consumption has increased(40) (and also perhaps as a result of increased cannabinoid content of cannabis in the past twenty years(41)). However, despite an increase in cannabis use in Australia (particular amongst teenagers) over the past 30 years, there does not appear to have been a corresponding rise in the prevalence of schizophrenia’.(42)

Conclusion

The evidence reviewed above suggests that cannabis use is associated with the development of mental disorders such as schizophrenia and depression. However, there is ongoing debate over exactly how this association should be characterised. In brief, it appears that while the majority of cannabis users will not develop mental illnesses as a consequence of their cannabis use, a ‘vulnerable minority appear to be at increased risk of experiencing harmful outcomes’.(43) As noted above, there is good evidence that young people and heavy users are particularly at risk.
The public-policy implications of this are complex. According to a recent review, the main challenge will be in communicating with young people about the probable risks of cannabis use:

This task will be complicated by the conflicting interpretations of the evidence on either side of the policy debate about the legal status of cannabis. We can expect those who defend current policy to support a strong causal interpretation of the evidence and proponents of cannabis liberalization to dismiss the evidence as the latest version of ‘reefer madness’. These contrasting responses may amplify scepticism among young people about messages about the mental health risks of cannabis use.(44)

In other words, it is crucial that emerging evidence about the links between cannabis use and mental-health problems is communicated clearly (particularly to those most at risk) and in a way that acknowledges the complexity of the issues involved without obscuring the level and gravity of the risks posed by cannabis use to vulnerable groups.

Acknowledgements

Thanks to Dr Louisa Degenhardt, National Drug and Alcohol Research Centre; Dr Jon Jureidini and Dr Ben Wells, Psychological Medicine, Women and Children’s Hospital, Adelaide; and Dr Stephen Rosenman, St. Vincent’s Hospital, Sydney/St John of God Hospital, Burwood; and Parliamentary Library staff who provided helpful comments on earlier drafts of this Research Note. The authors remain responsible for any errors and omissions.
1. J. Rey and C. Tennant, editorial, ‘Cannabis and mental health’, British Medical Journal, 325, November 2002, pp. 1183–84.
2. J. Rey, M. Sawer, B. Raphael, G. Patton and M. Lynskey, ‘Mental health of teenagers who use cannabis: Results of an Australian survey’, British Journal of Psychiatry, 180, 2002, pp. 216–21.
3. Australian Institute of Health and Welfare (AIHW), 2004 National Drug Strategy Household Survey: Detailed Findings, AIHW, Canberra, 2005, p. 42.
4. ibid.
5. I. Hickie, ‘Teenagers in greatest danger from cannabis-induced psychosis’, Weekend Australian, 5 November 2005, p. 31.
6. A. Johns, ‘Psychiatric Effects of Cannabis’, British Journal of Psychiatry, 170, 2001, pp. 116-22; W. Swift, J. Copeland and S. Lenton, ‘Cannabis and Harm Reduction’, Drug and Alcohol Review, 19, 2000, pp. 101–12.
7. W. Hall and L. Degenhardt, ‘Cannabis Use and Psychosis: A Review of Clinical and Epidemiological Evidence’, Australian and New Zealand Journal of Psychiatry, 43, 2000, pp. 26–34; W. Hall and N. Solowij, ‘The Adverse Effects of Cannabis’, Lancet, 352, 1998, pp. 1611–16.
8. ‘psychosis’, A Dictionary of Sociology, Oxford University Press, 2005.
9. C. Henquet, L. Krabbendam, J. Spauwen, C. Kaplan, R. Lieb, H. Wittchen and J. van Os, ‘Prospective cohort study of cannabis use, predisposition for psychosis, and psychotic symptoms in young people’, British Medical Journal, 330, January 2005, pp. 11–14.
10. Mental Health Council of Australia (MHCA), Where there’s smoke… - Cannabis and Mental Health, MHCA, Canberra, 2006, p. 23.
11. W. Hall, L. Degenhardt and M. Teesson, ‘Cannabis use and psychotic disorders: an update’, Drug and Alcohol Review, 23, 2004, pp. 433–43.
12. MHCA, op. cit., p. 23.
13. ibid., p. 23.
14. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit., pp. 433–43.
15. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit., p. 440. See also D. Basu, A. Malhotra, A. Bhagat and V. Varma, ‘Cannabis psychosis and acute schizophrenia: a case-control study from India’, European Addiction Research, 5, 1999, pp. 71–3.
16. A. Tien and J. Anthony, ‘Epidemiological Analysis of Alcohol and Drug Use as Risk Factors for Psychotic Experiences’, Journal of Nervous and Mental Disorders, 178, 1998, pp. 473–80.
17. D. Fergusson, R. Poulton, P. Smith and J. Boden, ‘Cannabis and psychosis’, British Medical Journal, 332, 2006, p. 173; Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit., p. 440; A. Johns, op. cit.
18. Henquet et al., op. cit., p. 13.
19. ibid., pp. 11–14.
20. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit., pp. 440–1.
21. Fergusson et al., ‘Cannabis and psychosis’, op. cit., p. 173.
22. G. Lawton, ‘Too much, too young’, New Scientist, 26 March 2005, pp. 45–6.
23. Fergusson et al, ‘Cannabis and psychosis’, op. cit., p. 174. See also W. Hall et al, ‘Cannabis use and psychotic disorders: an update’, op. cit., p. 440.
24. H. Moore, A. West and A. Grace, ‘The regulation of forebrain dopamine transmission: relevance to the pathophysiology and psychopathology of schizophrenia’, Biological Psychiatry, 46, 1999, pp. 40–55; G. Tanda, F. Pontieri and G. Di Chiara, ‘Cannabinoid and heroin activation of mesolimbic dopamine transmission by a common μ1 opioid receptor mechanism’, Science, 276, 1997, pp. 2048–50.
25. B. Raphael and S. Wooding, ‘Comorbidity: cannabis and complexity’, Of Substance, 2:1, January 2004, p. 11.
26. Rey et al., ‘Mental health of teenagers who use cannabis: Results of an Australian survey’, op. cit.
27. Rey and Tennant, op. cit. For additional examples, see H. Kalant, ‘Adverse effects of cannabis on health: an update of the literature since 1996’, Progress in Neuro-Psychopharmacology and Biological Psychiatry, 28, 2004, p. 855.
28. See, for example: Raphael and Wooding, op. cit. See also W. Compton, B. Grant, J. Colliver, M. Glantz and F. Stinson, ‘Prevalence of marijuana use disorders in the United States, 1991–92 and 2001–2002’, Journal of the American Medical Association, 291:17, 5 May 2004, pp. 2114–21.
29. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit. See also Raphael and Wooding, op. cit.
30. Henquet et al., ‘Prospective cohort study of cannabis use, predisposition for psychosis, and psychotic symptoms in young people’, op. cit.
31. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit.
32. ibid.
33. Kalant, op. cit., p. 856.
34. R. McGee, S. Williams, R. Poulton and T. Moffat, ‘A longitudinal study of cannabis use and mental health from adolescence to early adulthood’, Addiction, 95, pp. 491–3.
35. Kalant, op. cit., p. 856; D. Fergusson et al., ‘Cannabis and psychosis’, op. cit., p. 173; Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit., pp. 439–40.
36. ‘Psychological distress’ was measured using the Kessler 10 Scale of Psychological Distress. AIHW, Mental health services in Australia 2003–04, AIHW, Canberra, 2005, pp.15–16.
37. AIHW, 2004 National Drug Strategy Household Survey: Detailed Findings, op. cit., p. 97.
38. Dr John Macleod, co-author of the report, quoted in C. Huggins, ‘Cannabis Use Not Linked with Psychosocial Harm’, Reuters, 17 May 2004. See J. Macleod, R. Oakes, A. Copello, I. Crome, M. Egger, M. Hickman, T. Oppenkowski, H. Stokes-Lampard, G. Smith, ‘Psychological and social sequelae of cannabis and other illicit drug use by young people: a systematic review of longitudinal, general population studies’, The Lancet, 363, 2004, pp. 1579–88.
39. D. Fergusson, L. Horwood and E. Ridder, ‘Tests of causal linkages between cannabis use and psychotic symptoms’, Addiction, 100, 2005, pp. 354–66.
40. G. Lawton, op. cit., p. 47.
41. Rey et al., ‘Mental health of teenagers who use cannabis: Results of an Australian survey’, op. cit.
42. G. Lawton, op. cit., p. 47.
43. Hall et al., ‘Cannabis use and psychotic disorders: an update’, op. cit.
44. ibid., p. 441.

Reputation Comments on this post:

	Some interesting information, which deals with this complex subject in a scientific and neutral way
	Very good post
	Excellent, concise post on an important and often discussed issue.

[Lehendakari]

There is only one thing I agree with: Psychoactives should not be taken till one is an adult.

And by psychoactives I also include amphetamines, methylphenidate, antidepressants and tranquilizers and some other crap doctors give 7 years old kids as candy

[DeleteriousEffects]

Correlation does not equal causation.

[FuBai]

In my opinon there is little doubt that cannabis can initiate mental health problems. I would also say that the self medication hypothesis does have some truth in it. I would say that Marijuana probably either triggers underlying faults to grow into fissures, or that it retards the brain's ability to comabt underlying mental health issues that would have been far more mild otherwise. There is no point denying that Marijuana, like any drug, can cause damage. The very fact that it causes damage is why it must be leaglised and regulated. Never let the prohibitionists convince you that the health risks of any drug are sufficient cause for it to be banned - they are sufficient cause to think carefuly before taking it. Don't get bogged down in debating medical statistics because that's not the issue. The issue is far, far bigger than that.

[Nature Boy]

Retarding the brain's ability to cope with underlying mental health issues? That doesn't quite sound right. Perhaps to suggest that it may expose underlying mental issues would be a little more accurate. Suggesting that it "retards" (nice verb there) suggests that it causes brain damage which has been proven that it does not.

The trouble with assessing the positives and the negatives of cannabis is that each and every strain is different. Some are high in THC, which produces anxiety in some and euphoria in others. Other strains contain various cannabinoids that help reduce anxiety and have painkilling properties.

The actual amount of truly significant cases where people suffer from mental difficulty when using cannabis is also difficult to assess. A 15 year-old kid who's smoked a spliff once in his life and happens to get caught can easily be sent to a rehabilitation clinic and become another statistic without having suffered any psychological crisis. It's very difficult to tell how potentially dangerous something is when the statistics are endlessly biased.

[FuBai]

I was actualy thinking of two possible mechanisms by which cannabis could cause mental health problems - the first was as you explained, that it may cause underlying minor problems to become exposed. But the second idea was that, when you smoke cannabis you de-activate or impair the parts of your brain that may repress/supress mental health conditions. Imagine a cracked bowl held together with glue - there are two obvious ways the crack could become a problem - if it grew in size (option 1) or if the glue stopped working or became too weak (option 2).

[Nature Boy]

The great problem with people who develop mental difficulty with cannabis is that they don't realise their limits. They dive in recklessly and continue to use it despite not enjoying it anymore. Anxiety and paranoia can easily be overcome with some deep breathing and a simple reminder to oneself that they have absolutely no reason to feel that way unless they have a real reason to be worried e.g. running into law enforcement whilst stoned. If they still feel paranoid after practising this, they should probably not use it anymore or at the very least find a strain with more of the anxiety-reducing cannabinoids.

The same goes for someone who cannot simply have one or two drinks on a night out but must continue drinking until they drop. A lack of self-control in irresponsible hands is a dangerous thing. Moreso in the case of alcohol IMO, but it can apply to cannabis although how widespread this problem is may be greatly exaggerated.

[FuBai]

Originally Posted by Nature Boy

The great problem with people who develop mental difficulty with cannabis is that they don't realise their limits. They dive in recklessly and continue to use it despite not enjoying it anymore. Anxiety and paranoia can easily be overcome with some deep breathing and a simple reminder to oneself that they have absolutely no reason to feel that way unless they have a real reason to be worried e.g. running into law enforcement whilst stoned. If they still feel paranoid after practising this, they should probably not use it anymore or at the very least find a strain with more of the anxiety-reducing cannabinoids.

The same goes for someone who cannot simply have one or two drinks on a night out but must continue drinking until they drop. A lack of self-control in irresponsible hands is a dangerous thing. Moreso in the case of alcohol IMO, but it can apply to cannabis although how widespread this problem is may be greatly exaggerated.

Whilst I have never touched cannabis or the vile liquor, my friend Xenophon Zanzibar tells me, in regards to over indulgence, he finds it very hard to partake too heavily of cannabis - he always reaches a point where he just doesn't want to take anymore, and would just prefer to roll with it and let the acrid burning in his thoat die down. But with regards alcohol he often finds it very difficult to stop.
He once made the mistake of consuming 1 litre of cheap vodka, starting at 12 noon and ending at 12 midnight. He woke up drunk the next day, almost fell over getting out of bed because, once he's drunk, he just want's to get more drunk.

In regards to mental health issues, Xenophon has suffered from depression to the extent that he was almost admitted to a hospital - but this began before he had ever used anything more than alcohol and caffine. It was only subsequent to his depressive period that he began drug use. For him it was entirley self-medication, not causation.

[imyourlittlebare]

I have up some facts on this thread if youd like to see. http://www.drugs-forum.com/forum/s...443#post339443

But pretty much the basis of my argument that is well backed up by facts is

1. Linked to schizophrenia- You have to be predisposed to having schizo to get it. Its a complex process. But since dopamine and glutamate activity is effected by pot and those are the two main neurotransmitters that are being researched for schizo then the facts support it does play a heavy role
2. "Cannabis withdrawal" which is an increase of anxiety that lasts weeks or months or years. Some say it doesnt exist. Most heavy smokers who stop dont get WD right away. Here is my interpratation of a correlation. THC takes a month to get out of your system. Pots half life is very long. It fully takes a month to get out. As the days turn into weeks your anxiety increases (read in the human studies part in the thread i posted it validates it as well as many people i know). So there is a type of withdrawal going on. It is an intense and generalized anxiety that was manifested after pot was discontinued and yes it was caused by pot. the research shows that pot causes brain changes that set someone up for generalized anxiety disorder with panic attacks through effecting Dopamine and Glutamate as well as causing tolerance at GABA receptors to occur
3. Short term memory is hurt. youve seen the studies that show pot users grow new hippocampal cells? well they are finding this is due to the fact that THC causes deficits in Short term mem (stm) and the brain is adapting. Its growing new cells to make up for its loss. This is applicable to alot of things. Brain scans show pot abusers use much more of there brain. Bc there smarter? no because deficits caused by pot require the brain to adapt and change how it works

Reputation Comments on this post:

Posting the same thing everywhere = spam!

[toe]

Originally Posted by FuBai

But the second idea was that, when you smoke cannabis you de-activate or impair the parts of your brain that may repress/supress mental health conditions. Imagine a cracked bowl held together with glue - there are two obvious ways the crack could become a problem - if it grew in size (option 1) or if the glue stopped working or became too weak (option 2).

What SWIFuBai seems to be missing here, is the fact that there is an expiration date DNA-imprinted for the glue in biochemically disordered brains. Certain disorders, like bipolar I and schizophrenia, almost universally have "failure" dates falling within the span of young adulthood, between the 20s and 30s. Of course any individual is a unique case- a combination of "lesser" brain disorders could hit a child before he even enters grade school, leaving him hopeless about his future and unable to utilize his potential by 14. OTOH bipolar disorder can be turned from a university student's worst nightmare into a duel career as a clinical psychologist and a writer. (Assuming one is as fortunate & bright as Kay Redfield Jameson.)

As mentioned above, there is no evidence that marijuana causes any permanent alteration in the brain function of an adult user. There is plenty of evidence of it's temporary effects- unfortunately propaganda has allowed the scales of justice to tip against fair representation of the positive/neutral effects. (There are *arguably* entire classes of prescription medications that cause equal/greater impairment of cognitive function on a temporary basis while causing permanent damage in a disturbing number of cases- anti-psychotics, to start with.)

Anecdotally, ST memory repairs itself within a couple of weeks of ceasing chronic use. LT memory- learning- never appeared to have been an issue. Alcohol, in comparison, was found to be vastly more damaging to learning capacity and basic cognitive agility, as demonstrated by qualitative comparison of rehearsed analytical skills and newly acquired qualitative skills at the commencement and cessation of a one week period of abstinence from alcohol. (Hey, the study was done in Russia!) Of course the carcinogenic MOA utilized most frequently for cannabis ingestion brings it's safety back into question, but hopefully oral use can be reccommended.

At any rate, "dopamine and glutamate activity is effected by pot and those are the two main neurotransmitters that are being researched for schizo then the facts support it does play a heavy role" definitely does not hold water. Unless you want to blame marijuana for causing epilepsy, meth addiction, dementia, parkinson's disease, eating disorders, circadian-rhythm disorders, aging, nicotine & cocaine addiction, tinnitus. Admittedly, there's been evidence presented that shows sufficient evidence of correlation between certain human maladies and marijuana use to be considered more or less solid, but "dopamine and glutamate are affected by marijuana and have something to do with schizophrenia" is an ineffective argument.

Levels of the endocannabinoid anandamide were elevated in cerebrospinal fluids of first-time diagnosed schizophrenics who had smoked up to 5 times, verses those who had smoked more than 20 times. CSF anandamide levels correlated inversely with psychotic symptoms, in addition to which levels were found to be quite a bit higher in schizophrenic patients than in healthy volunteers. The study concludes that smoking marijuana causes a down-regulation of endocannabinoids in schizophrenics, but not healthy volunteers.

Apparently, substance abuse is fairly co-morbid with mental illness. Nonetheless, there are numerous publications refuting the correlation-as-causation link. This study concludes that:

The socio-demographic characteristics of cannabis abuse or dependence in schizophrenia are similar to those found in general population. Cannabis using schizophrenic patients were more likely to be younger and male than non users. The duration of hospitalization was significantly longer for the group with cannabis abuse. Prevalence of suicide attempts in schizophrenia is closely correlated to cannabis abuse.

This study would seem to imply that continued substance abuse- while clearly not helpful at all in the case of anxiety and depression- does not inhibit response of schizophrenic symptoms to treatment.

Apparently, cannabinoids stimulate a release of norepinephrine , as well.

My houseplants happen to believe that these issues can't be so neatly tied up. There are too many rabbit holes to fall down, too many skeletons in the closet. That drug use can exacerbate existing mental illness is clear, but it's certainly not going to send anyone over the edge who wasn't ultimately going to wind up there, anyway. And there are too many completely idiopathic cases of major mental illness to even hope that we'll ever whittle down the causes to any number of subtypes.

[Nature Boy]

Originally Posted by imyourlittlebare

Here is my interpratation of a correlation. THC takes a month to get out of your system. Pots half life is very long. It fully takes a month to get out. As the days turn into weeks your anxiety increases (read in the human studies part in the thread i posted it validates it as well as many people i know). So there is a type of withdrawal going on. It is an intense and generalized anxiety that was manifested after pot was discontinued and yes it was caused by pot.

By pot or by lack of pot? That suggesting this theory is in any way true.

[imyourlittlebare]

Sorry I hadnt seen this. Im a wreck lately. And i still need pdfs. As the thc leaves the body. Thats what causes the anxiety. Thats not the only cause of anxiety due to the initial days of people having anxiety but I would imagine that that is a mixture between habitual learning and this same phenomenon. That is, not replenishing the stores to keep the GABA systems from working on its own in the cannabis system. Thats the psychological addiction. While this whole mess was caused by using pot in the first place heavily, the lack of pot is what causes this anxiety. Because like i said, pots half life 12 days. Out of your system in 30. Anxiety is at its worst a month later. Same as total thc depletion. So its a lack of pot its gotta be. Environemental factors may play a part on how bad the anxiety is. I mean if your in honalulu and going through this. You may be on edge and hate people, but hopefully the anxiety doesnt include panic attacks (if your predisposed to them) and you can still go on with your life. If shit is stressful then its a tough thing to go through on top of environment. I wouldnt know if this causes panic attacks with the anxiety. Because swim has panic attacks that are totally biological so Swim would heir on the side there is a chance of getting them without use. But for the most part, panic attacks seem to be caused by
1. Not facing fears/dealing with shit and it builds up and confronts you
2. Biological
3. Irrational thoughts.

[plur]

yes and no

1.yes in that it worseness per-exsiting problem to the point that may requir hosplization

2.no, only becouse the data is incunclive with peolpe without per-exsiting
conditions (opion)


*1 is based on personal exspearnce

[Drug Add1ct]

it does take down brain cells... and that causes it.... lol and also if you put other stuff into yes... but remeber we dont have unlimited brain cells thats the only cell that cant reduce itself or w/e or how ever you say it... lol any of this help?? in anyway??? :P

Reputation Comments on this post:

Misinformation.

[Nature Boy]

^^^

Wrong. Cannabis does not reduce or increase the amount of brain cells. It acts on brain receptors. Totally different thing.

[Drug Add1ct]

well i dont really know ^^ sorry mate my bad

[vantranist]

From SWIMs own usage, he is pretty sure that mj can really mess ur head up, Mainly if you are already fuked up.

[methMADMAN]

What THC, the active chemical in marijuana does in the brain has nothing to do with killing brain cells. It is fat soluble and what part of the brain isn't water is mostly made up of fat. THC gums up the passage ways in the brain between the neurotransmitters. Normally this isn't a serious issue, but some heavy smokers develop serious short term memory problems. Nobody knows why it's so different for different folks, but in extremely rare and serious cases, some heavy users have had to write all they do in notebooks, because they literally cannot remember what happened five minutes ago. This level of impairment is extremely rare, but it has happened. It is likely that in such cases the condition is not wholly caused by THC, but perhaps only aggravated by it. Nobody knows for sure how much it clears up or how fast, but it is generally thought that after some period of abstinence, the condition returns to normal in most people.

[Nature Boy]

^^^

That is absolutely laughable. Goldfish memory is it? Could you provide some documentation backing that up? Novice users may experience memory problems but most regular smokers adapt and overcome these minor obstacles. If you haven't noticed, in the modern world, people don't rely on memory much. That's why we have notebooks and computers. The ancient Greeks developed incredible systems to manage mental memory for lack of being able to record information. Impressive as those techniques were, they're largely unneeded in this day and age.

[Shampoo]

What THC, the active chemical in marijuana does in the brain has nothing to do with killing brain cells.

True

It is fat soluble and what part of the brain isn't water is mostly made up of fat.

Lipid solubility is a necessity for crossing the blood-brain-barrier and many other membranes that lack large fenestrations.

THC gums up the passage ways in the brain between the neurotransmitters.

Please provide scientific evidence for this theory. How could THC 'gum up the passage ways'? and what 'passage ways' are you referring to? It sounds like you are implying that THC sits in the synaptic cleft, depot-bound to NT bonding sites, preventing excitation from normal sources. If this is the proposal, it is incorrect. First of all, memory exists neurologically in a different path of neurotransmitters and proteins than cannabis is active through, and second of all, cannabis works as an agonist of CB (cannabinoid) receptors throughout the body with an average binding affinity and excretion time. It does not somehow remain in the synaptic cleft or anywhere else active, but rather is converted into the inactive THC-COOH and excreted. THC exerts its effects on memory through manipulation of the endogenous cannabinoid system, including modulation of the endocannabinoid Anandimide. Short-term memory disturbances are also medicinally documented as one of the first symptoms to which a tolerance is developed. After several consecutive days of smoking, almost all patient and users experience a return to normal states of memory due to a 'rebound' effect by the endocannabinoid system.

Normally this isn't a serious issue, but some heavy smokers develop serious short term memory problems. Nobody knows why it's so different for different folks, but in extremely rare and serious cases, some heavy users have had to write all they do in notebooks, because they literally cannot remember what happened five minutes ago. This level of impairment is extremely rare, but it has happened. It is likely that in such cases the condition is not wholly caused by THC, but perhaps only aggravated by it. Nobody knows for sure how much it clears up or how fast, but it is generally thought that after some period of abstinence, the condition returns to normal in most people.

This sounds like an old wives' tale. Please provide some documentation when proposing outlandish, extreme theories like this. First of all, if someone's memory was being completely obliterated by cannabis, a non-addictive substance, why would they continue to use it? Because they already forgot? This seems like a gross-misunderstanding of the neurological functions underlying memory. Memory is not a single system awaiting obliteration from some single chemical reaction, it is a multi-faceted, chemical and electrical reaction spread out throughout the brain that results in a variety of manifestations, including short and long-term-potentiation.

[methMADMAN]

No, you go research it. I have researched it enough. The fact is that facts could hit you in the face and you would refuse to believe because it isn't what you want to be true. I am done talking to potheads. It's boring to bounce around in debates with people who only believe what they want to believe.

methMADMAN added 4 Minutes and 43 Seconds later...

Not that it stands a snowballs chance in hell of reaching you, but this was pretty easy to find.....

Reputation Comments on this post:

	grow up
	ignorant
	This post is overly-aggressive, immature, and does not contribute to the quality of information on this forum. If you ca...

[Shampoo]

No, you go research it. I have researched it enough. The fact is that facts could hit you in the face and you would refuse to believe because it isn't what you want to be true. I am done talking to potheads. It's boring to bounce around in debates with people who only believe what they want to believe.

It is very unfortunate that you feel an appropriate, mature dialogue concerning this issue cannot be pursued. There is no correct answer to this question, that is why studies are constantly being conducted to determine the legitimacy of claims on either side. Giving evidence like you have done below is a great way to legitimize the claims that you make, just as those on the other side should do as well if prompted. Rather than simply shooting down someone's idea, why not ask for evidence? If they cannot provide evidence, then your concept clearly has a superior grounding. This would be far more productive than name calling and emotionally heated, personally aggressive responses. I am more than willing to consider all of your points if you present them in a mature, appropriate manner.

Not that it stands a snowballs chance in hell of reaching you, but this was pretty easy to find.....

A very interesting study with a legitimate, neurological explanation for the short-term memory loss associated with THC and the inhibition of LTP. Much better than, 'gums up the passageways' since this is clearly not what is happening. There are opposing studies, specifically on the cannabinoid HU-211, exhibiting the neuroprotective agency of cannabinoids. The debate seems very analogous to that regarding cannabis's ability to induce cancerous cell growth, which due to its carcinogen content seems probable, however further (mostly government funded) study has since revealed that with a symbiotic chemistry between the carcinogenic properties of smoke and the cancer-growth-inhibition properties of THC, cannabis posed no threat of increasing cancer-related risks. Similarly, while THC has been shown to interfere with calcium release (thereby reducing NT release, slowing LTP), behavioral and neurological examinations have contrarily shown that tolerance and adaptation to these effects is almost immediate with prolonged exposure.

Additionally, after a little more research it appears most of these effects are only observed during intoxication, or when THC is actually bound to CB receptors in the hippocampus. If this is the case, then evidence in favor of it leading to mental-health problems is a little far-fetched, though if these effects are in fact prolonged after intoxication (the studies I have found say they are not) then it seems like a good point. The general medical consensus seems to be however, that prolonged exposure creates an absolute tolerance for the amnestic effects of cannabinoids.

Reputation Comments on this post:

	Interesting.
	Well, that's just an excellent post sir!

[Zoso]

)))))))))))))))))))Greetings(((((((((((((((((((

Isn't this sometimes called the Syd Barrett syndrome.That is if you're gonna develop mental health problems (predisposition) then anything with psycho active properties is gonna hurry those problems along and exacerbate them .
>>>>>>>>>>>>>Be seeing you<<<<<<<<<<<<<<<<<<<
))))Zoso((((

[sirdrugalot]

yeah swim smoked it for 15 years, for 13 every day. he started thinking people could read his mind, thought he was saying the things he was thinking in his head out loud. if he was standing in line at say the post office he would think people behind and around him were talking in some kind of funny coded language and laughing about him. in the end he stopped smoking would not leave the house which made things even worse. it was only when he made a break for it and got a job started talking to people it all started to go away. started smoking again surprise, surprise they came back stopped and they went away again.
yeah and his memory is fucked not to the extent that he has to write every thing down that he has to do with a pen and paper, but all ways forgets things he has to buy when in town, leaves the car key in the ignition, lock him self out of the house things like that.
so yeah it dose cause mental health problems.

[Frost og Taake]

Heyo, Swim has schizophrenia and had it before swim used any sort of mind altering drug. Its interesting to say the least. Comparing to swims friends, he found that cannabis seems to have stronger effects. When paranoia kicks it...Swim cant leave the house, he cant walk around, he cant be seen. However, when the effects are positive, swim finds the effects to be GLORIOUS. He acts like a "normal" person. I would also assume that the kind of schizophrenia one would have would react more to cannabis then other sorts. In other words, the hallucinating sorts would probbably become stronger but no more...horrible. However the kind that are paranoid and think they are being followed would indeed get horrible senses of dread and possibly further their schizophrenic deliriums. Just my thought. by the way, SWIm isnt a doctor, just a user of cannabis and aquired schizophrenia.