Cannabis for Pain

Cannabis, which is used to make hemp and marijuana, has therapeutic potential in pain medicine, a new study suggests.

Researchers from Peninsula Medical School, Plymouth, UK, explained that advances in cannabis research have paralleled developments in opioid pharmacology, whereby a psychoactive plant extract has revealed new endogenous signaling systems with therapeutic significance.

Cannabinoids (CBs) are chemical compounds derived from cannabis. The major psychoactive constituent of Cannabis sativa, delta(9)-tetrahydrocannabinol (THC), and endogenous cannabinoid ligands, such as anandamide, signal through G-protein-coupled cannabinoid receptors localized to regions of the brain associated with important neurological processes. Signaling is mostly inhibitory and suggests a role for cannabinoids as therapeutic agents in CNS disease where the inhibition of neurotransmitter release would be beneficial, report the researchers.

The review observed that clinical trials of CBs in multiple sclerosis have suggested a benefit in neuropathic pain. However, human studies of CB-mediated pain relief have been limited by study size, heterogeneous patient populations and subjective outcome measures. Furthermore, CBs have variable pharmacokinetics and can manifest psychotropism. They are currently licensed as medications that prevent nausea and vomiting in chemotherapy and can be prescribed on a named-patient basis for neuropathic pain.

The authors concluded that cannabis has future potential in pain medicine.

Comments

[mo]

This is definitely a very interesting area. The endocannabinoid system, the system in the brain that is activated by smoking marijuana, can be manipulated in many ways, apparently. While activating endocannabinoid receptors is associated with increased appetite, for example, appetite can be decreased by blocking this activation. There is an obesity drug that is available in Europe (but not the US) that does just this. Part of why it’s not yet available in the US, however, is due to the potential for psychological side effects. When you think about it, it makes sense. Activating these receptors causes pleasure, so blocking them causes the opposite effect. This effect is particularly pronounced in people with a history of depression or in people who take antidepressants.

[liz]

What about for other conditions like HIV or cancer? Which is better- smoking or eating or pills? Haworth used to publish the Journal of International Hemp Research I believe - may be some interesting data to explore there, I'm not sure if it is Medline listed though.

[Chelsea]

I wish medicinal marijuana was not such a controversial topic. There are many potential benefits. Plus, Canadian researchers recently found that it's associated with few adverse effects (http://www.upi.com/Health_News/2008/06/17/Few_medical_marijuana_adverse_events/UPI-90901213732188/). According to the study authors, most non-serious adverse events observed involved dizziness and drowsiness.

[TJ]

Here's an interesting article on medicinal marijuana: http://tierneylab.blogs.nytimes.com/2008/06/11/medical-marijuana-links/ It links to several great stories on the topic

[Rob]

I'd like to see more marijuana research with vaporizers. It's unfortunate that scientists are limited because they only have access to a small supply of marijuana available from the only legal source - a federal farm in Mississippi.

[Joe]

Hopefully, more studies like this will help legalize medicinal marijuana in more states. If you use a vaporizer, you get the same benefits minus many of the adverse effects.

[YN]

This is definitely exciting since it would be another reason for making marijuana legal in many states. Despite the fact that it works by antagonizing the endocannabinoid receptors, one should take cannabinoid’s potency into consideration. How much is enough? Thus, the problem with dependence may then be solved.

However, every drug has its own drawbacks. Like someone mentioned - the euphoric effect could be reversed with cannabinoid. We should always take into account those MS patients with depression comorbid, but, does it necessarily mean that we have to exclude them?

[ATAD]

I found this article, “Marijuana Use Sparks Liver Transplant Controversy,” to be quite interesting. It has actually been noted that patients with hepatitis C who are engaging in legal medical marijuana to combat against the symptoms of their disease, as well as to aid in their nausea from their antiretroviral treatments, are actually being denied a spot on the liver transplant list. Nevertheless, the principle of deciding who will receive transplantation has become scrutinized and essentially has become an ethical debate. I have attached the link of where I found the article if I have peaked anyone’s interest. http://www.hepatitis-central.com/mt/archives/2008/06/marijuana_use_s.html

[DT]

Hopefully, there will be more studies on this. With more studies and strong data support, the more physicians will use it. I just worry about overuse and addiction.

[Emma]

This is an interesting topic, and I have found some good information here. I know very little about cannabis except that it is used medicinally to treat a number of diseases such as cancer, glaucoma and AIDS.

[Jane]

It has been known for a long time that cannabis is a pain reliever - although perhaps the investigation into MS is new. Did you know medical marijuana is legal in California? Recently, there was an article about UMass trying to get more funding / ability to conduct more studies on cannabis - I'm not sure of the final ruling. An herbalist friend also told me that just putting the leaves in a bath would eliminate chronic pain, so it's interesting that this herb works via many routes of administration, although who knows what is placebo effect and what is real. Also - to answer someone's question above - I think when they make cannabis pills they omit the THC, which causes the euphoria. So the agents should be considered viable agents and really - this notion of "illegal" should be placed in perspective with its potential use as a pain reliever. Here is a bunch of information I found on Medical Marijuana: http://www.erowid.org/plants/cannabis/cannabis_medical.shtml

[Aunique]

This is the perfect of example of how many things, if not all, have plus and minus characteristics. I wonder if the people who reject the positive properties of this substance out of some "moral" imperative are equally unhappy that a daily glass of wine (and this does not even take on the use of wine in religious rituals) can offer some health protection, when we all know that a bottle or two of wine can cause a multitude of health and social problems. And bottom line, where is the moral high ground of denying relief to a suffering individual?

[bla]

In regard to Rob’s concern, I have found this article http://www.ncbi.nlm.nih.gov/pubmed/18645719?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum. It is not about a vaporizer. Interestingly, people are trying to study how much of delta(9)-tetrahydrocannabinol is produced through smoking condensate. Unfortunately, there is only abstract for this study, but I thought you might be interested anyway.

[anna]

Not only can this substance be used to aid in nausea associated with chemotherapy and improve pain, but it can also reduce intraocular pressure in the eyes facilitating in glaucoma treatment. This discovery has become a research phenomenon. Thus, medications containing cannabinoids that can be put directly on the eyes, but not result in the mind-altering effects, are currently being investigated.

[abby]

There is evidence to support the use of cannabis for its appetite-stimulating. This agent has proven to be a benefit in AIDS patients who are developing wasting (severe weight-loss). This agent has also has been famed to generate spiritual, psychosomatic and physical benefits namely due to its autonomic nervous system effects, which expands breathing, ensuing in total body relaxation

[sunflowers]

I have seen many people who suffered extreme pain due to neuropathy (diabetes, cancer). Hopefully, it will be legal soon for medical purpose used. One of the articles I had read said too much cannabis can "worsen pain". http://news.bbc.co.uk/2/hi/health/7058193.stm

[houhou]

I found this very recent article regarding the ongoing debate about whether or not marijuana should be legalized. http://cannabisnews.com/news/24/thread24089.shtml It does not matter how you look at it. I think marijuana should be legal for medicinal purposes only. Clinical studies like this one have shown the analgesic and many other effects of marijuana. What else are we waiting for while other analgesics are run down because of tolerance and dependence?

[Children Anxiety Disorder]

I think that makes sense because when you use marijuana, you feel better. So maybe it is as useful at pain-relieving medications. If you accept morphine, why can't you accept cannabis???