'Cannabis' acts as antidepressant

A chemical found in cannabis can act like an antidepressant, researchers have found.

A team from Canada's University of Sasketchewan suggest the compound causes nerve cells to regenerate.

The Journal of Clinical Investigation study showed rats given a cannabinoid were less anxious and less depressed.

But UK experts warned other conflicting research had linked cannabis, and other cannabinoids, to an increased risk of depression and anxiety.

They suggested this could be because different cannabinoids acting at different levels have contradictory effects.

Cannabinoids have been shown to relieve the symptoms of multiple sclerosis and pain relief in humans.

The Canadian researchers gave rats injections of high levels of one artificial cannabinoid, HU210, for a month.

The animals were seen to have nerve cell regeneration in the hippocampus, which is linked to memory and emotions.

The hippocampus has been shown to generate new nerve cells throughout a person's or an animal's life, but this ability is reduced if cells are engineered to lack a cannabinoid receptor protein called CB-1.

In the Canadian study, rats given the cannabinoid were also found to be less anxious, and more willing to eat food in new environments - a change which would normally frighten them.

However, research has previously linked use of the drug cannabis to long-term damage to mental health, and to increase the risk of mental illness in those who are already genetically susceptible.

In addition, short-term high doses of cannabinoids had also been shown to produce anxiety-like effects in rats and depression-like effects in mice.

But other studies had found that low-doses of cannabinoids helped to reduce anxiety in rodents.

The Canadian team said: "These complicated effects of high and low doses of acute and chronic exposure to cannabinoids may explain the seemingly conflicting results observed in clinical studies regarding the effects of cannabinoid on anxiety and depression."

Professor Robin Murray, of the Institute of Psychiatry, questioned whether the anti-anxiety and antidepressant effects seen in the animals would be replicated in humans.

He said: "This is a very big leap of faith as they have no data on humans, and the supposed animals' models of anxiety and depression that they use don't have much in common with the human conditions."

Paul Corry, Director of campaigns and communication at Rethink said: "Cannabinoids are an exciting new area for medical research, but it is important to recognise that there are over 60 active ingredients in cannabis - synthetic cannabinoid may be showing evidence of nerve regeneration.

"But as also pointed out in this study, the effects of cannabis on the brain are complex and produce conflicting evidence.

"For most people with severe mental illness, raw cannabis remains a risky substance.

"All medical research needs to be checked before it would make a difference to the hundreds of thousands of people living with severe mental illness in the UK."

Psychosis, Hype And Baloney

The mainstream media is eating it up, but a new study claiming a link between marijuana use and psychosis should be approached with great caution.
As the month began, the worldwide press jumped all over a study in the March issue of the journal Addiction purporting to show a causal link between marijuana use and psychosis. "Drug Doubles Mental Health Risk," the BBC reported. "Marijuana Increases Risk of Psychosis," the Washington Times chimed in.

Such purported links have lately become the darling of prohibitionists, but a close look at the new study reveals gaping holes unmentioned in those definitive-sounding headlines.

Before we look at the study itself, let's consider some basics: If X causes Y, it's reasonable to expect a huge increase in X to cause at least a modest increase in Y, but this has not been the case with marijuana and psychosis. Private and government surveys have documented a massive increase in marijuana use, particularly by young people, during the 1960s and '70s, but no corresponding increase in psychosis was ever reported. This strongly suggests that if marijuana use plays any role in triggering psychosis, that effect is weak, rare, or both.

For this reason, researchers should approach "proof" that marijuana causes serious mental illness with great caution. The researchers in this case, a New Zealand team led by David M. Fergusson of the Christchurch School of Medicine and Health Sciences, seem to have done just the reverse.

Fergusson's team looked at a group of 1,265 New Zealand kids who were followed from birth to age 25 and assessed at various points along the way for a variety of physical, mental and social problems and issues. At ages 18, 21 and 25 they were assessed for both marijuana use and supposed psychotic symptoms. Having found a correlation, with daily users reporting the highest frequency of psychotic symptoms, they then applied a series of mathematical models. These models are designed to adjust for possible variables that might confound the results and to assess whether the marijuana use caused the symptoms or vice versa.

Whatever model was applied, the correlation held up. But the reported "growing evidence" that "regular use of cannabis may increase risks of psychosis" depends completely on the validity of the underlying data, and those data raise some screamingly obvious questions.

Psychotic symptoms were measured using 10 items from something called Symptom Checklist 90. Participants were asked if they had certain ideas, feelings or beliefs that commonly accompany psychotic states. The researchers did not look at actual diagnoses, and the symptom checklist is not identical to the formal diagnostic criteria listed in the DSM-IV manual. Perhaps most important, they only used 10 "representative" items from a much larger questionnaire.

These 10 items focus heavily on paranoid thoughts or feelings, such as "feeling other people cannot be trusted," "feeling you are being watched or talked about by others," "having ideas or beliefs that others do not share." This presents a big methodological problem, because it is well known that paranoid feelings are a fairly common effect of being high on marijuana.

But the article gives no indication that respondents were asked to distinguish between feelings experienced while high and feelings experienced at other times. Thus, we are left with no indication at all as to whether these supposed psychotic symptoms are long-term effects or simply the normal, passing effects of marijuana intoxication. While it's possible the researchers had these data and didn't see a need to report them, the failure to do so is downright bizarre. It's like reporting that people who go to bars are more erratic drivers than people who don't, without bothering to look at whether they'd been drinking at the time their driving skills were assessed.

Even if these were long-term effects, the researchers seem not to have considered that what might be an indication of psychosis in other circumstances could be an entirely normal reaction for people who use marijuana. Consider: Someone using a substance that is both illegal and socially frowned-upon almost by definition has "ideas or beliefs that others do not share." This is not a sign of mental illness. It's a sign of a rational person realistically assessing his or her situation.

The same goes for "feeling other people cannot be trusted." Just ask Robin Prosser, the Montana medical marijuana patient arrested last summer on possession charges by the cops who came to save her life after she'd attempted suicide because she was in unbearable pain after running out of medicine.

Fergusson reports very little raw data, so we don't know which symptoms came up most often, or whether the differences in average levels of symptoms between users and non-users came from a few people having a lot of symptoms or a lot of people having a couple symptoms. The heavy-user group, with the highest levels of supposed psychosis, reported an average of less than two symptoms each. So it is entirely possible that the entire case for marijuana "causing" psychosis is based on marijuana smokers having the completely reasonable feelings that they have beliefs different from mainstream society and thus should be a tad suspicious of others.

"Proof" that marijuana makes you psychotic? No. Not even close. But don't expect the mainstream media to figure this out.

Bruce Mirken is communications director for the Marijuana Policy Project. Mitch Earleywine, Ph.D., is associate professor of psychology at the University of Southern California and author of "Understanding Marijuana" (Oxford University Press, 2002).

I had no experience with marijuana thirty years ago, but I did smoke a little as early as twenty seven years ago and I can tell you there was plenty of strong pot out there back then. It may vary well be that the average is a little higher than it was twenty years ago, and that the strongest marijuana is stronger than the strongest of twenty years ago, but it all does the same thing. Unless it's just so weak that it makes you sleepy and gives you a headache before it ever gets you high, it will all do the same thing if you smoke enough of it. The marijuana of today is not some new drug. Just like beer and distilled spirits are the same drug that will do the same thing, stronger marijuana and weaker marijuana are the same. And just as it works with alcohol, people tend to consume less of the stronger marijuana than they would of he weaker stuff.

As for marijuana making everyone crazy, I just don't believe it. I could see how people with mental illness would gravitate toward marijuana just as they gravitate toward other intoxicants in an attempt to get some relief from their difficult miserable lives, and I could see how like other intoxicants it might exacerbate an existing condition, but I haven't seen any solid proof that it actually causes mental illness. All we really have in these studies is proof of a link, proof of correlation, but not proof of causation.

It seems to me that if marijuana is really making so many people crazy, we'd have a much higher instance of serious mental illness in states with higher rates of marijuana use than in states with the lowest rates of use. In order to test this theory, I looked at data from the The U.S. Department of Health and Human Services' Substance Abuse and Mental Health Services Administration (SAMHSA), which collects data on both mental illness and drug use. My thinking was that if marijuana really causes serious mental illness, there would be correspondingly higher rates of mental illness in states with higher rates of marijuana use. Doesn't that make sense?

First I looked at the state with the highest past month marijuana use, New Hampshire. In that state 10.23% reported use of marijuana in the past month on the last survey and and according to SAMHSA 8.8% of New Hampshire's population suffer from serious mental illness compared to the national average of 8.76%. Then I looked at the state with the lowest marijuana use, Utah. There only 4.00% reported past month marijuana use but SAMHSA says 10.97% suffer from serious mental illness.

Now, that was interesting to me but there are too many variables that can come into play that call into question the results from just two examples. So, I dug a little deeper and looked at the ten states with the highest and ten states with the lowest marijuana use. The national average past month marijuana use was 6.18%. The top ten states averaged 8.93%. Serious mental illness in these states averaged 8.73%, compared to the national average of 8.76%. Serious mental illness in the ten states with the lowest marijuana use averaged 9.44%, even though past month marijuana use only averaged 4.73% in these states.

Why is it that the states with the highest marijuana use actually lower rates of serious mental illness than the states with the lowest marijuana use? I honestly don't know. I don't think you could conclude from that that marijuana use reduces mental illness, but it certainly does call into question research that shows that marijuana use drastically increases mental illness.

Here are the tables I used from SAMHSA's 2003 NSDUH. The link to the past month marijuana use by state is here: http://www.oas.samhsa.gov/2k3State/appB.htm#tabB.3

The link to the serious mental illness numbers by state is here: http://www.oas.samhsa.gov/2k3State/appB.htm#tabB.21 "

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.