Weeding out the highs of medical marijuana

Jul 15, 2008

Research exploring new ways of exploiting the full medicinal uses of cannabis while avoiding unwanted side-effects will be presented to pharmacologists today (Tuesday, 15 July) by leading scientists attending the Federation of European Pharmacological Societies Congress, EPHAR 2008.

Cannabis is a source of compounds known as cannabinoids, one of which, THC – the main chemical responsible for the 'high' – has long been licensed as a medicine for suppressing nausea produced by chemotherapy and for stimulating appetite, for instance, in AIDS patients.

More recently, the cannabis-based medicine Sativex was licensed both for the symptomatic relief of neuropathic pain in adults with multiple sclerosis and as an adjunctive analgesic treatment for adult patients with advanced cancer. Sativex contains approximately equal amounts of THC and the non-psychoactive plant cannabinoid, cannabidiol.

"THC works by targeting molecules in our bodies called cannabinoid receptors" said Roger Pertwee, Professor of Neuropharmacology at the University of Aberdeen, who is co-chairing the cannabis symposium.

"So some current research is focused on designing drugs that only target cannabinoid receptors in the part of the body relevant to the disease in question and not the receptors in the central nervous system involved in the unwanted effects of cannabis."

A further approach to avoiding the psychoactivity caused by THC involves harnessing the body's own cannabis, called 'endocannabinoids'.

"We don't have cannabinoid receptors just in case we come into contact with plant-derived chemicals that activate them but rather because we have our own molecules that do this," said Christopher Fowler, Professor of Pharmacology at Umea University, in Sweden, and co-chair of the meeting.

"The neat thing about endocannabinoids is that they are often produced only when we need them, such as when our bodies are damaged in some way; pain, for example, leads to a release of endocannabinoids in a region of the brain that is involved with pain control.

"The problem with this natural protective 'endocannabinoid system' is that it is too short-lived to be of great benefit – enzymes in our bodies quickly breakdown or metabolise the endocannabinoids negating their effect. It's a bit like a bathtub without a plug – the water is turned on but rapidly disappears down the plughole. This suggests an immediate target: block the plughole and the water will stay longer.

"Since the release of endocannabinoids is local, levels in other parts of the brain, stay low. This approach is under intense investigation and programmes for the development of new drugs targeting pain and possibly other disorders such as anxiety and depression are currently underway."

Speakers will report on promising studies that show improved strategies for targeting the endocannabinoid system, not only for pain relief, but also for treating other conditions, including stroke, liver diseases and, ironically, nicotine addiction and obesity.

Thus, as the conference will hear, there are some disorders in which endocannabinoid release appears to be detrimental to our health, one example being obesity, which can be treated with Acomplia*, a licensed synthetic medicine that acts by blocking cannabinoid receptors.

Professor Pertwee added: "THC in cannabis is of course well known for its ability to induce 'the munchies' and, as mentioned, is used in clinics to boost appetite. But my research group has discovered that another constituent of cannabis, THCV, acts in a similar way to Acomplia, blocking one of the cannabinoid receptors, so providing an alternative – and potentially better – treatment route in the fight against obesity.

"The conference will hear about some of the possible advantages THVC has over current obesity treatments, as well as data on the potential of cannabinoids to treat other conditions, including neurodegenerative disorders like Alzheimer's, Parkinson's and Huntington's disease."

Source: University of Manchester

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Bonkers
5 / 5 (4) Jul 15, 2008
There are many issues here, no wonder that nobody got into the heat of it for so long - its a bit crazy for medicine to ignore a whole chemical system for 30 years, but they did.

Firstly there's the ready availability - Big Pharma can't see how to get its money from testing a common plant, this leads to re-inventing the active substances to make saleable and differentiated commercial products. if ever there was a case for government-backed research for the common good, then this it.

Then there s the whole medic's phobia about prescribing useful drugs with "fun" properties - if penicillin made you giggle you wouldn't get it, my theory is that this is a reaction to the hilariously embarrassing "treatment" meted out to fretful wives at the turn of the century, steam-powered of course, check out "hysterical paroxysms".

Then there is the "war against drugs" - any notion that Marijuana has some beneficial properties undermines the "evil" argument, and creates a legitimate need, complicating prohibition.

Its time to allow individuals to grow an amount for their own use - much like home-brewing of beer, this works OK doesn't it?
Its not right for a government to apply a one-size-fits-all policy, people are different, reasonable use is simply that.
Egnite
1.5 / 5 (2) Jul 15, 2008
Excellent news, for the pharma companies and fussy people! Bad news for those already addicted to "medical marijuana" who'll have to get thier high from criminals instead. I won't be buying natural (but altered) substances from pharma companies, that's for sure!
snwboardn
4 / 5 (4) Jul 15, 2008
Way to ruin marijuana... "The unwanted side effects?" Such as getting high and enjoying yourself? It all boils down to money, if you can't market it and the government can't tax it. But it makes you feel good, it's bad. I've seen a lot of people blame it on Christianity too, but most Christians I know feel that it is a plant that God put here for us to enjoy. So the only thing I can think of is greedy government.
nilbud
4.3 / 5 (4) Jul 15, 2008
@Egnite Noone gets addicted to marijuana, it's not addictive.
Just ignore the stupid rules made up by long dead puritan assholes, they were the imbeciles who thought prohibition was a good idea and created the mafia as a result. If you don't like to smoke you can cook with buds. THC is fat soluble so crush buds up and sprinkle it into some melted butter which can then be added to anything you're cooking. It works better on back pain than Ibuprofen.
COCO
1.7 / 5 (3) Jul 16, 2008
Marajuana is the gate way drug to heroin - there can be no research or need so wonderful as to place people's lives in the balance. One has only to look to Amsterdam to see the chaos and destruction of the weed! We must encourge active enforcement of current laws and try to imprison as many users as possible to teach them a lesson about freedom!!
Benhole
1 / 5 (2) Jul 20, 2008
Yeah, great idea COCO. We should also murder people to teach a lesson about killing, and rape them to teach them a lesson about abstinence. And by the way, you spelled Marijuana wrong, idiot.
LargeHCollider
5 / 5 (1) Jul 20, 2008
I am not sure how I feel about the subject at hand except that anything that can help life be happier and more productive can't be all that bad. However, one thing I am quite sure of, COCO has never been to Amsterdam. Frankly I am surprised he/she knew enough to capitalize the name!!!
Quik98
not rated yet Feb 21, 2009
COCO your an idiot. I smoke marijuana everyday with dose-relation, and I play hockey, Get A and B's in college whereas before I was a "pothead" I got C's D's and F's in high school. Another example, Michael Phelps. Marijuana doesnt lead to heroin, I wont touch that S**t. Marijuana IS a gateway in the sense it can let people know what they brain can do. Alcohol and Tobacco are just as much of a gateway. It can also be a gateway in the sens that the person is crossing the line of legality and so the person might start experimenting more and theya rent afraid to get caught. There is a cure for that problem, LEGALIZE!
Quik98
not rated yet Feb 21, 2009
I find it has helped me to focus and inspires me to excel and fight for what I want. The point is not to get blasted, 2-3 puffs every 3 hours will make you inspired will motivate you, put you in a good mood, and help you to focus.

I use it for ADHD and anxiety related issues but it has done more for me than alleviate those symptoms. Its time we start studying the cannabis plant properly. With expanding medical marijuana research, we should be able to make a final decision once and for all.