Cannabis: Minor Chronic Effects

John H. john at faraway.com
Tue Jul 1 02:53:06 EST 2003


Damn right Ian, many studies now point to powerful benefits for
cannabinoids. Unfortunately when cannabis is mentioned people only think of
THC and particuarly in the USA the political climate is absurd. Eg. Some
months ago the DEA issued a notice to pet shop owners to remove all birdseed
products with pot seed in it ... . By the way, good evidence that
dicannabidol(spelling!) should be extensively trialled for stroke and head
trauma victims. Its ability to save neurons is remarkable, has
anti-inflammatory properties, in vitro toxicity is impossible (or at least
have never been demonstrated). There is also good evidence to for
cannabinoid antitumoural properties (breast, glioma, prostrate) but won't
hear that in the news ... .

By way of contrast, look at the studies on alcohol.




Ian, thanks for these posts, you usually throw up some interesting stuff.


John H.



--
johnYYYcoe at tpg.com.au

remove YYY in reply
"Ian Goddard" <igoddard at erols.mom> wrote in message
news:hkq0gv8gpgh43kjnpgisjtlul8svnvrk2m at 4ax.com...
>
>  Cannabis prohibition is a persistent social tragedy,
>  especially in light of the fact that it is far safer
>  than legal alcohol. Cannabis prohibition is most
>  pernicious in light of its efficacy in treating a
>  range of ailments with a safety profile that exceeds
>  criteria for "safe" applied to legal prescription drugs.
>
>
> http://health.ucsd.edu/news/2003/06_27_Grant.html
>
> Minimal Long-Term Effects Of Marijuana Use Found in Central Nervous
> System by UCSD Researchers
>
> An analysis of research studies with long-term, recreational users of
> marijuana has failed to reveal a substantial, systematic effect on the
> neurocognitive functioning of users. According to researchers at the
> University of California, San Diego (UCSD) School of Medicine, the
> only deleterious side effect found was a minimal malfunction in the
> domains of learning and forgetting.
>
> The findings were particularly significant considering the movement by
> several states to make cannabis (marijuana) available as a medicinal
> drug, and questions regarding its potential toxicity over long-term
> usage.
>
> Published in the July issue of the Journal of the International
> Neuropsychological Society, the study involved a quantitative
> synthesis of 15 previously published research studies on the non-acute
> (residual) effects of cannabis on the neurocognitive performance of
> adult human subjects.
>
> The studies included 704 long-term cannabis users and 484 non-users.
> The neurocognitive performance measurements included simple reaction
> time, attention, verbal/language, abstraction/executive functioning,
> perceptual/motor skills, motor skills, learning and forgetting.
>
> "Surprisingly, we saw very little evidence of deleterious effects. The
> only exception was a very small effect in learning new information,"
> said Igor Grant, M.D., the study's senior author, a UCSD professor of
> psychiatry, and director of the Center for Medicinal Cannabis Research
> (CMCR), a collaborative, state-supported program between UCSD and UC
> San Francisco, that oversees 11 studies of the safety and efficacy of
> medicinal cannabis to treat certain diseases.
>
> In describing the negative effects in the study, the research team
> said the problems observed in learning and forgetting suggest that
> chronic long-term cannabis use results in selective memory defects.
> They added that "while the results are compatible with this
> conclusion, the effected size for both domains was of a very small
> magnitude."
>
> Grant added that the minimal side effects seen "raised the question of
> practical significance. If we barely find this tiny effect in
> long-term heavy users of cannabis, then we are unlikely to see
> deleterious side effects in individuals who receive cannabis for a
> short time in a medical setting."
>
> In addition, Grant said that heavy marijuana users often abuse other
> drugs, such as alcohol and amphetamines, which also might have
> long-term neurological effects. This raises the question of the extent
> to which the other drugs contributed to the minimal problems found in
> learning and forgetting in the marijuana users.
>
> The paper's authors also noted that many of the research studies
> examined had significant limitations, either with small numbers of
> subjects or insufficient information about potential confounding
> factors, such as exposure to other drugs or presence of
> neuropsychiatric factors such as depression or personality disorders.
>
> They noted that only studies that begin with the examination of
> children and young adolescents before they enter the period of risk to
> cannabis exposure, can sufficiently reduce the influence of these
> additional factors.
>
> In addition to Grant, the paper's authors included doctoral students
> Raul Gonzalez, M.S., and Catherine L. Carey, M.S. and Loki Natarajan,
> Ph.D., UCSD HIV Neurobehavioral Research Center (HNRC) and UCSD
> Department of Family and Preventive Medicine, and Tanya Wolfson, M.A.,
> UCSD HNRC.
>
> The study was supported by the CMRC.
>
> ##
>
>
> Study: Pot Doesn't Cause Permanent Brain Damage
>
> Fri June 27, 2003 12:18 AM ET
>
> By Deena Beasley
>
> LOS ANGELES (Reuters) - Smoking marijuana will certainly affect
> perception, but it does not cause permanent brain damage, researchers
> from the University of California at San Diego said on Friday in a
> study.
>
> "The findings were kind of a surprise. One might have expected to see
> more impairment of higher mental function," said Dr. Igor Grant, a
> UCSD professor of psychiatry and the study's lead author. Other
> illegal drugs, or even alcohol, can cause brain damage.
>
> His team analyzed data from 15 previously published, controlled
> studies into the impact of long-term, recreational cannabis use on the
> neurocognitive ability of adults.
>
> The studies tested the mental functions of routine pot smokers, but
> not while they were actually high, Grant said.
>
> The results, published in the July issue of the Journal of the
> International Neuropsychological Society, show that marijuana has only
> a marginally harmful long-term effect on learning and memory.
>
> No effect at all was seen on other functions, including reaction time,
> attention, language, reasoning ability, and perceptual and motor
> skills.
>
> Grant said the findings are particularly significant amid questions
> about marijuana's long-term toxicity now that several states are
> considering whether to make it available as a medicinal drug.
>
> In California, growing marijuana for medical purposes is legal under a
> voter-approved law.
>
> The UCSD analysis of studies involving 704 long-term cannabis users
> and 484 nonusers was sponsored by a state-supported program that
> oversees research into the use of cannabis to treat certain diseases.
>
> Anecdotal evidence has shown that marijuana can help ease pain in
> patients with diseases like multiple sclerosis or prevent severe
> nausea in cancer patients, but the effects have yet to be proven in
> controlled studies, Grant said.
>
> The UCSD research team said the problems observed in learning and
> forgetting suggest that long-term marijuana use results in selective
> memory defects, but said the impact was of a very small magnitude.
>
> "If we barely find this tiny effect in long-term heavy users of
> cannabis, then we are unlikely to see deleterious side effects in
> individuals who receive cannabis for a short time in a medical
> setting," Grant said.
>
> In addition, he noted that heavy marijuana users often abuse other
> drugs, such as alcohol and amphetamines, which also might have
> long-term neurological effects.
>
> Some of the research studies used in the analysis were limited by the
> numbers of subjects or insufficient information about factors like
> exposure to other drugs or whether participants suffered from
> conditions like depression or personality disorders.
>
> "If it turned out that new studies find that cannabis is helpful in
> treating some medical conditions, this enables us to see a marginal
> level of safety," Grant said.
>
>
http://www.reuters.com/newsArticle.jhtml;jsessionid=4OYPTFA0MLHGWCRBAEZSFEY?
type=scienceNews&storyID=2998963
>
>
>   http://IanGoddard.net/philo.htm
>
>   "Our greatest illusion is to believe that we are what
>    we think ourselves to be." Henri Amiel (1821-1881)
>
>





More information about the Neur-sci mailing list