Legalizing pot might be good from a public health perspective, but that doesn’t make marijuana a miracle cure
Marijuana has a special place in our cultural consciousness. It’s the drug of choice for rebellious teens, partly because it makes pizza taste really good, but also because it’s easy to get a hold of and according to the guy with the hemp bag from down the street, totally safe.
Also, getting high is fun. I hear.
But even more than that, marijuana carries an aura of legitimacy — it’s not just a drug, it’s a natural drug, and we all know that natural things are better for our health. We are constantly bombarded with the idea that pot is more than just a great way to spend an afternoon: it’s saving lives.
Except, that’s definitely not the whole story.
There are some medical uses for marijuana but they are probably far less impressive that you may have heard.
If you look around, you can find pretty claims that marijuana can cure pretty much every disease under the sun. Nausea? Marijuana is apparently a first-line treatment that everyone should use. Anxiety? Take two joints daily, because weed can temporarily stop that too. Diabetes? It seems like cannabis can prevent or even potentially treat the disease.
Some people even claim that the magical plant can cure cancer, which would be huge if true.
But while these claims are widespread, there’s a central problem here. Many of them are based on anecdotes, or lab-bench research that has very little relevance to our lives. Even the arguments about marijuana that do carry some weight, like the idea that it might help with psychosis, have often only been tested in tiny groups of people, and often have not actually been found to be that effective anyway.
Another issue is that people often conflate any drugs that are derived from marijuana with the plant itself. For example, there’s the case of Epidiolex, which is a drug that has been developed using cannabidiol, a component of cannabis. It contains a “highly purified” form of cannabidiol, which is a far cry from the original raw material, and yet still often lumped into the basket of ‘medical marijuana’.
You could just as easily argue that aspirin is a willow bark treatment, or that morphine is nothing more than simple poppies.
The reality is that many of the uses of medical marijuana are look far more like traditional medications than smoking a joint, not least because smoking is bad for your health regardless of what you’re smoking. There are also issues of potency and effect — cannabis is made up of hundreds of chemicals, but often only one or two are effective for treating disease. It’s very hard to ensure you’re actually getting the right combination without at least testing for consistency first.
Which brings us to the most important question: what is medical marijuana effective for?
The answer? Not all that much.
Despite all the hype, there are basically three conditions that marijuana has been properly tested in humans for: chronic (non-cancer) pain, chemotherapy-induced nausea, and epilepsy. Let’s look at all three:
- Chronic Pain: there’s a lot of hype about cannabis for chronic pain, but the evidence paints a different story. A recent systematic review including nearly one hundred studies found that there were modest benefits associated with cannabis use, but these were probably outweighed by the negatives. If 100 people used marijuana to control their pain, about 4 would have a clinically significant reduction in symptoms, but nearly 20 would experience side-effects, of which about half (10 people) would be severe enough that they’d stop the treatment. Other systematic reviews have similar findings — for some people, marijuana may be an effective pain reliever, but it doesn’t work for everybody, and it causes a lot of problems for some.
- Epilepsy: this is probably the biggest hope for marijuana — everyone has heard the stories of children saved from certain doom by the wonderful power of weed. And here, the science is pretty optimistic — recent studies have shown that cannabis does indeed have an effect on epilepsy. While the effect is much more modest than many headlines would have you believe, and the evidence isn’t that good quality, the science does seems to indicate that marijuana can potentially reduce the number of seizures that people with epilepsy experience.
- Chemotherapy-related nausea: nausea is a tricky one, because there’s strong evidence from a range of studies that marijuana makes some people nauseous. However, there‘s a lot of anecdotal data that it can treat nausea for some people as well, in particular those undergoing chemotherapy for treatment of their cancer. Thus far studies have been divided — while there does appear to be some evidence that certain drugs derived from cannabis can treat nausea symptoms, the studies aren’t very good and it’s hard to know if the results are accurate or not. This makes the issue a bit tricky — we are pretty sure that marijuana can cause nausea, but we don’t know yet if it can treat it too.
And that’s pretty much it. There are dozens of other conditions that marijuana is claimed to cure, but we in reality we only know about these three, and even here the evidence isn’t great. Epilepsy seems like the best bet, but it’s hard to know exactly how effective weed is using our current evidence, particularly when the actual drugs used under the medical marijuana umbrella are pretty diverse.
Which this brings us to an issue I mentioned earlier — “medical marijuana” is a pretty ridiculous blanket term. It covers everything from people smoking hand-rolled joints to complex formulations of marijuana extracts. Some of these are undoubtedly useful for the treatment of some diseases, but you can’t take the results from a study of, say, concentrated dronabinol and apply them to every other product containing marijuana out there.
Any Other Drug
The bottom line is that weed is essentially just like every other drug — it probably works for some things, doesn’t work for others, and causes side-effects that can be very serious for some people.
In other words, medical marijuana has both pros and cons.
For some people — particularly those with incurable conditions — weed might be an amazing solution to their problems. But for most, it’s just another option that has both positives and negatives.
There’s a strong harm-reduction argument behind legalizing marijuana for recreational use — regulating the drug while dropping the criminal element is almost certainly a positive for society. But that doesn’t make it a miracle cure.
Marijuana might be a lot of fun, but it’s no panacea.
The evidence shows that it’s really just another drug.
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