December 20, 2012
Marijuana Isn’t a Pain Killer—It’s a Pain Distracter
A new study indicates that marijuana isn’t a painkiller, but a pain distracter: Under the influence of THC, the same levels of pain are simply less bothersome. Image via Wikimedia Commons/Cannabis Training University
One of the chief arguments for the legalization of medicinal marijuana is its usefulness as a pain reliever. For many cancer and AIDS patients across the 19 states where medicinal use of the drug has been legalized, it has proven to be a valuable tool in managing chronic pain—in some cases working for patients for which conventional painkillers are ineffective.
To determine exactly how cannabis relieves pain, a group of Oxford researchers used healthy volunteers, an MRI machine and doses of THC, the active ingredient in marijuana. Their findings, published today in the journal Pain, suggest something counterintuitive: that the drug doesn’t so much reduce pain as make the same level of pain more bearable.
“Cannabis does not seem to act like a conventional pain medicine,” Michael Lee, an Oxford neuroscientist and lead author of the paper, said in a statement. “Brain imaging shows little reduction in the brain regions that code for the sensation of pain, which is what we tend to see with drugs like opiates. Instead, cannabis appears to mainly affect the emotional reaction to pain in a highly variable way.”
As part of the study, Lee and colleagues recruited 12 healthy volunteers who said they’d never used marijuana before and gave each one either a THC tablet or a placebo. Then, to trigger a consistent level of pain, they rubbed a cream on the volunteers’ legs that included 1% capsaicin, the compound found that makes chili peppers spicy; in this case, it caused a burning sensation on the skin.
When the researchers asked each person to report both the intensity and the unpleasantness of the pain—in other words, how much it physically burned and how much this level of burning bothered them—they came to the surprising finding. “We found that with THC, on average people didn’t report any change in the burn, but the pain bothered them less,” Lee said.
This indicates that marijuana doesn’t function as a pain killer as much as a pain distracter: Objectively, levels of pain remain the same for someone under the influence of THC, but it simply bothers the person less. It’s difficult to draw especially broad conclusions from a study with a sample size of just 12 participants, but the results were still surprising.
Each of the participants was also put in an MRI machine—so the researchers could try to pinpoint which areas of the brain seemed to be involved in THC’s pain relieving processes—and the results backed up the theory. Changes in brain activity due to THC involved areas such as the anterior mid-cingulate cortex, believed to be involved in the emotional aspects of pain, rather than other areas implicated in the direct physical perception of it.
Additionally, the researchers found that THC’s effectiveness in reducing the unpleasantness of pain varied greatly between individuals—another characteristic that sets it apart from typical painkillers. For some participants, it made the capsaicin cream much less bothersome, while for others, it had little effect.
The MRI scans supported this observation, too: Those more affected by the THC demonstrated more brain activity connecting their right amydala and a part of the cortex known as the primary sensorimotor area. The researchers say that this finding could perhaps be used as a diagnostic tool, indicating for which patients THC could be most effective as a pain treatment medicine.
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“”CBD (Cannabidiol). It is one of approximately 70 Cannabinoids, the most well known being THC. CBD is an amazing compound, it can be used to treat chronic pain, anxiety and other mood disorders, as well as being a neuro-protectant and a very promising anti-cancer drug. CBD’s value in treating chronic pain is enhanced over THC because it is non-psychoactive.
CBD works against pain primarily in the peripheral nervous system. It does not work like typical pain meds by effecting the central nervous system; it works at the neuro-synapse. When we sustain injuries, often the pain is acute and disappears completely. Other times we have persistent or intermittent pain, however, with many disorders the pain is either part of the underlying problem itself (Multiple Sclerosis, Rheumatoid Disease, etc ) or the pain becomes a syndrome of it’s own. In other words, the pain takes on a life of it’s own and is now crippling the patient.”"
From: http://canchewbiotech.com/pain-management-and-cbd
There’s case studies clinical trials in the website posted above. Please get educated; stop the propaganda.
THC is not the only active component in Cannabis. There are 483 different identifiable chemical constituents known to exist in cannabis.
Almost sounds preferable to me. Killing pain altogether can be dangerous, your body uses it to inform you of problems for a reason.
Well this misses the point entirely, doesn’t it? Does anyone who knows anything about this field (even as a layman) really expect THC to be the saviour when it comes to pain?
@Midian: Plenty of people are already well aware that there is a problem and could really do with a break from the pain to help them either (a) deal with said problem or (b) continue to live a normal life.
Certainly, there are many other active components in Cannabis, but when they are all mixed together in the natural herb, they affect each other’s action, and make it harder to link particular effects to any one chemical. Now that the researchers have a baseline for how THC affects brain activity, they should compare these results to those obtained from patients using the whole herb.
were there healthy volunteers, meat-eaters?
I think if they looked at vegan or vegetarians, they might come to different conclusions.
Hey Sam,
Where did you learn that vegans and vegetarians had nervous systems that functioned differently than meat-eaters?
@Gustavo: “CBD works against pain primarily in the peripheral nervous system. It does not work like typical pain meds by effecting the central nervous system; it works at the neuro-synapse.”
This statement doesn’t make much sense. You say that CBD does not affect the central nervous system like most pain meds, but then you say it works at the neuro-synapse. First, the brain (which contains these “neuro-synapses” which are the small gaps between neurons where messages are transmitted) is part of the central nervous system. Second, the synapses are where ALL medicinal/drug effects take place in the brain. Thus, based on what you stated, CBD would work like other pain meds.
@sam
Just, please… stop typing. Please read some books on communication and critical thinking and then come back to the internet.
Anyone who is familiar with marijuana could have told you this was the case, I’m surprised the researchers found this to be a new development. Why would people think its a painkiller in the first place? The researchers are obviously pretty uninformed
Sam, how so? What would be the difference between veg*s and meat eaters?
No they were not vegans, it says they chose *healthy* volunteers. Also, this has no bearing on this unimpressive study…
Anything that helps. I hate suffering!
well dude, that’s like…your opinion…man
You did forget to mention CBDs, which have been credited as providing the pain killing effects we find in certain strains of cannabis. If my memory serves me. . . THC is responsible for the psychoactive effects which provide us with the indicators that the cannabis is effective. CBDs on the other hand for me is less detectable even in percentages as high as 10% which is hard to find in most strains, only the ones specifically cultivated for their pain killing properties such as the strain Harlequin. I’m no doctor, but who wrote this article that fails to mention the other chemicals besides the widely known THC?
This reminds me of the old fable about the drunk man searching on hands and knees for something under a street lamp late one night
A friend of his walks by and asks him what he’s doing on his hands and knees in the dark…
The drunk man answers “searching for my key”
So the friend helps the drunk man and starts to look around for the lost key
After a number of minutes, the friend asks, “Where exactly did you drop it?”
The drunk man waves his arm back toward the darkness. “Over there, in my house.”
The friend, bewildered, asks, “Then why are you looking for it out here?”
“Because there is more light here than inside my house.”
~~~~~~~~~~~~~~~~~
had they used the entire plant (containing all of the cannabinoids) in their research instead of merely THC tablets they might have discovered something much more useful.
Wow, significant bias shown in this ‘science’, and no mention of the relaxant or vasodilation effects of marijuana – these two characteristics alone can account for the treatment of most common types of muscle pain and migraine. If the blood-viscosity ruducing effects of asprin are considered to be analgesic, then so must the vasodilation effects of marijuana, which is arguably far more effective.
Why does this not just make it a different type of “pain killer”? Our everyday conception of pain seems to be a bit confused when you split the previously simple concept into multiple parts.
Ex.) What does this mean, “same level of pain”?
A child who is scared of getting a shot will experience more pain from the act because the body has been conditioned to create a larger pain response to the same level of input. This is not merely a matter of perception, but it actually hurts more. Comparing this child to one who is not scared, is their “level of pain” the same? If yes, does that not seem misleading considering one is in more pain? If no, does marijuana work in this manner, and thus actually change the “level of pain” experienced?
@Sam: I’m curious where you’re going with this. What’s your idea?
Last paragraph – it’s amygdala, not amydala :)
This is not a study, this is propaganda. I wonder who is funding these people. From the methodology to the wording, it is clear that there is an agenda here to dismiss the use of medical marijuana. A serious study would have talked about affecting stimuli vs. affecting threshold, not about killing the pain vs. getting you distracted (high).
I have an injury right now and I tried both opioids and marijuana. I feel much less impaired with marijuana and can go through my day and work better. I’m also much less concerned with addiction, since opioids are much more addictive than marijuana.
You do have to be quite savvy to use marijuana, carefully chose a high CDB strain (please note the study uses only THC), carefully find the right dosage for you, etc. With opioids is much easier, you just give money to a big pharm company…
Opiate based meds which are over prescribed and wildly abused and addictive don’t kill pain either. They just make you not care that you are in pain.
I feel like this study is a little bit too conclusive based on the results. For one, saying that it is not like typical pain killers in the amount that individuals react to the drug is illogical, different people require different doses of pain killers to gain the same effect, so why would this not be the same with THC? Also, I have trouble trusting a study with 12 participants, in my opinion that is way too small of a sample size for a study containing as many variables as this.
This looks like a small but good study. The questions above, about this only testing one cannabinoid of the many in marijuana, is a good point. This is how science works, small building blocks of good, double blind studies adding knowledge to our baseline of understanding the world. Often leading to more questions (peer review).
If this is how MJ works in pain management it is a good thing! The side effects of narcotics in chronic pain treatment can be horrendous. Sounds like all physicians should consider MJ in combination with lower doses of narcotics for pain management over 3 days. We need some serious research in this country , kudos to these Oxford researchers.
“THC, the active ingredient in marijuana”
How does the world not know about CBD yet? THC this, THC that. CBD is the wonder ingredient that everybody needs to be talking about.
http://www.youtube.com/watch?v=31SrjjgPbhU
http://www.prnewswire.com/news-releases/can-cannabidiol-cbd-fight-metastatic-cancer-according-to-the-latest-research-the-answer-is-yes-170681736.html
The plants in the picture is in horrible shape you monsters! It hurts looking at them. Please fix them and take better care in the future. Thanks
Junk study. Gave them THC in a pill, not MJ in its natural form. So now we know that THC in pill form does not block pain in the same way as an opiates. And nothing more.
This article is trash.
The Smithsonean isn’t even credible. About anything. They have an agenda, their research reflects it, and they suck at hiding it to anyone who does 30 mins of research. They were even attacked at the TEDtalks.
I’ve been a chronic pain sufferer for twenty plus years and I agree that cannabis works best for me as a pain distracter. I’ve noted that in my stories when being published. But I think most important here is: it is effective in helping chronic pain sufferers cope with pain and improve their quality of life. We should not be concerned if it kills pain or not. It’s safe and effective and that is what is most important. Peace..DD
I also believe that the effect in pill form is different from that of the original way it is to be taken in the body. The pill already has something mixed into it to make it into medicinal form while the original has not been tainted thus giving the pure effects of the plant. Thus, this study has not really proven much since it is expected to yield a different result in the first place.
as someone with a chronic pain condition…i have used both opiates and cannabis…for ME opiates are pain distracters (as in they simply don’t work very well for me) while cannabis actually alleviates my pain. opiates and cannabis work on different bodily systems: opiates on the central nervous system and cannabis on the limbic system…
This is an interesting article, that I can personally identify with. I am not a pain patient (thank God since I am highly allergic to the opiod class drugs) but during one personal episode I found the use of marijuana to allow me to ignore the pain.
Thanks
Rob
Good article, the authors continue to write a better article!
Carl Balog
Since when should we accept anything published by any government agency? They all follow their stringent agenda that’s formulated by agencies who publish propaganda and studies that are aimed at a certain objective. Do you believe 100%, 80%, 50%, 20% of what this government tells the public?
Do your own DD and research independent agencies that are not backed by any govt.
$$$.