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.j...toryID=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)

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@tpg.com.au

remove YYY in reply
"Ian Goddard" <igoddard@erols.mom> wrote in message
news:hkq0gv8gpgh43kjnpgisjtlul8svnvrk2m@4ax.com...
type=scienceNews&storyID=2998963

http://health.ucsd.edu/news/2003/06_27_Grant.html

"John H." <john@faraway.com> wrote:

IAN: Here are a couple cannabidiol abstracts along
with a review of the pharmacology of cannabinoids
that concludes: "Properties of cannabis that might
be of therapeutic use include analgesia, muscle
relaxation, immunosuppression, sedation, improvement
of mood, stimulation of appetite, antiemesis, lowering
of intraocular pressure, bronchodilation, neuroprotection
and induction of apoptosis in cancer cells." Here's more:


J Clin Pharmacol. 2002 Nov;42(11 Suppl):11S-19S.

Cannabidiol: an overview of some pharmacological aspects.

Mechoulam R, Parker LA, Gallily R.

Department of Medicinal Chemistry and Natural Products, Hebrew
University of Jerusalem, Israel.

Over the past few years, considerable attention has focused on
cannabidiol (CBD), a major nonpsychotropic constituent of cannabis.
The authors present a review on the chemistry of CBD and discuss the
anticonvulsive, antianxiety, antipsychotic, antinausea, and
antirheumatoid arthritic properties of CBD. CBD does not bind to the
known cannabinoid receptors, and its mechanism of action is yet
unknown. It is possible that, in part at least, its effects are due to
its recently discovered inhibition of anandamide uptake and hydrolysis
and to its antioxidative effect.

http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

************************************************** ***

J Clin Pharmacol. 1981 Aug-Sep;21(8-9 Suppl):417S-427S.

Hypnotic and antiepileptic effects of cannabidiol.

Carlini EA, Cunha JM.

Clinical trials with cannabidiol (CBD) in healthy volunteers,
isomniacs, and epileptic patients conducted in the authors' laboratory
from 1972 up to the present are reviewed. Acute doses of cannabidiol
ranging from 10 to 600 mg and chronic administration of 10 mg for 20
days or 3 mg/kg/day for 30 days did not induce psychologic or physical
symptoms suggestive of psychotropic or toxic effects; however, several
volunteers complained of somnolence. Complementary laboratory tests
(EKG, blood pressure, and blood and urine analysis) revealed no sign
of toxicity. Doses of 40, 80, and 160 mg cannabidiol were compared to
placebo and 5 mg nitrazepam in 15 insomniac volunteers. Subjects
receiving 160 mg cannabidiol reported having slept significantly more
than those receiving placebo; the volunteers also reported
significantly less dream recall; with the three doses of cannabidiol
than with placebo. Fifteen patients suffering from secondary
generalized epilepsy refractory to known antiepileptic drugs received
either 200 to 300 mg cannabidiol daily or placebo for as long as 4.5
months. Seven out of the eight epileptics receiving cannabidiol had
improvement of their disease state, whereas only one placebo patient
improved.

http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

************************************************** ***

Clin Pharmacokinet. 2003;42(4):327-60.

Pharmacokinetics and pharmacodynamics of cannabinoids.

Grotenhermen F.

Nova-Institut, Hurth, Germany. franjo.grotenhermen@nova-institut.de

Delta(9)-Tetrahydrocannabinol (THC) is the main source of the
pharmacological effects caused by the consumption of cannabis, both
the marijuana-like action and the medicinal benefits of the plant.
However, its acid metabolite THC-COOH, the non-psychotropic
cannabidiol (CBD), several cannabinoid analogues and newly discovered
modulators of the endogenous cannabinoid system are also promising
candidates for clinical research and therapeutic uses. Cannabinoids
exert many effects through activation of G-protein-coupled cannabinoid
receptors in the brain and peripheral tissues. Additionally, there is
evidence for non-receptor-dependent mechanisms. Natural cannabis
products and single cannabinoids are usually inhaled or taken orally;
the rectal route, sublingual administration, transdermal delivery, eye
drops and aerosols have only been used in a few studies and are of
little relevance in practice today. The pharmacokinetics of THC vary
as a function of its route of administration. Pulmonary assimilation
of inhaled THC causes a maximum plasma concentration within minutes,
psychotropic effects start within seconds to a few minutes, reach a
maximum after 15-30 minutes, and taper off within 2-3 hours. Following
oral ingestion, psychotropic effects set in with a delay of 30-90
minutes, reach their maximum after 2-3 hours and last for about 4-12
hours, depending on dose and specific effect. At doses exceeding the
psychotropic threshold, ingestion of cannabis usually causes enhanced
well-being and relaxation with an intensification of ordinary sensory
experiences. The most important acute adverse effects caused by
overdosing are anxiety and panic attacks, and with regard to somatic
effects increased heart rate and changes in blood pressure. Regular
use of cannabis may lead to dependency and to a mild withdrawal
syndrome. The existence and the intensity of possible long-term
adverse effects on psyche and cognition, immune system, fertility and
pregnancy remain controversial. They are reported to be low in humans
and do not preclude legitimate therapeutic use of cannabis-based
drugs. Properties of cannabis that might be of therapeutic use include
analgesia, muscle relaxation, immunosuppression, sedation, improvement
of mood, stimulation of appetite, antiemesis, lowering of intraocular
pressure, bronchodilation, neuroprotection and induction of apoptosis
in cancer cells.

http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract



http://IanGoddard.net/journal.htm

"To lengthen thy life, lessen thy meals." Ben Franklin

Ongoing CR monkey study update: "In the monkeys...those on
reduced feeding since the study started are dying at a rate
that is about half that of the monkeys receiving a full food
ration." Associated Press: Eating less may extend human life.
August 1, 2002 : http://www.msnbc.com/news/788746.asp?0si=-