Cannabis is usually held up as a healthier drug when it comes to the illegal drugs. The common theories being:
1. It’s a plant
2. We have cannabinoid receptors in our bodies for that plant
3. It’s not addictive
4. It’s better for you than smoking
5. It’s a plausible treatment
1. Many drugs are from plants and they’ve been purified to obtain the active ingredient. The active ingredient is the chemical that is found to alter biological processes in the body and cause the “feeling” of the drug.
THC is the active ingredient of cannabis, and is in its most fundamental form a white powder, like everything else. Heroin is also from a plant, the poppy, they’ve just processed its seeds.
“Natural remedies” (e.g. St john’s wort) are often associated with lots more side effects and drug interactions because they’re impure and not as well studied.
Though it seems healthier to go natural, it’s not necessarily safer and can make your doctors life a bit of a nightmare!
2. The cannabinoid receptors in our brains serve the function of forgetting irrelevant information, regulating appetite, pain and mood. THC mimics the shape of a natural endocannabinoids.
A study in Norway showed that children who heavily smoked marijuana in their teens lost 8 points of IQ from when they were 13-38. The lost mental abilities did not return. Socioeconomic factors (their friends, family and wealth) may have played a role though.
Cannabis mildly produces dopamine (less so than cocaine), but the frequency of use of the drug is more frequent among users. Dopamine is a reward chemical, it’s released when you achieve something desirable (e.g. completing some work, winning a race).
However, if a user gets such a feeling of contentment from marijuana, it may make a person unmotivated to do any work or run any races.
3. Marijuana is considered to be socially addictive, meaning people often find they are mainly drawn to other people who smoke marijuana, so they have limited friends who do not. This can make quitting very difficult for some.
It’s called a “social addiction phenomenon”, in medicine it's called marijuana use disorder where cannabis makes up a large degree of their day to day life. It’s said to effect up to 30% of users.
4. Unfortunately, when you burn most things they produce carcinogens (things that cause cancer).
There’s less data to prove that marijuana causes cancer than smoking, but this is partially due to the fact that marijuana has younger user population, but there’s still strong evidence.
Vaporising is shown to be better and taking oral THC better still. The danger with vaporisers is it may make a marijuana use disorder more probable for the user.
They’ve found many regular smokers of cannabis developing a condition called COPD unusually early for example in their 20s. Amy Winehouse for example received a diagnosis at 24.
5. So, is cannabis an effective treatment? Yes!
- For chronic pain (pain over a long time) and spasticity there’s moderate evidence
- For Parkinson’s, Alzheimer’s and Huntington’s there’s mild evidence, but it’s worse than current treatments
- For cancer treatment there’s poor evidence (in rats)
Why are we hesitant to move to medical marijuana in the UK? One of the big reasons is 1 in 100 users experience adverse psychological effects (depression, anxiety, schizophrenia and bipolar).
Arguably, it’s hard to tell whether the cannabis causes mental illness or just people with mental illnesses are more likely to use cannabis.
Studies have come out that suggesting that cannabis use is associated with a significant risk of depression in adolescence. The same study showed no increase in interest in cannabis of mentally ill children.
Daily cannabis smokers were found to be 5 times more likely to have depression. However, why is there also some research (in rats) that suggests marijuana is a potential antidepressant?!
The reason the answer is confusing is data suggests it’s heavily dependent on dose. The problem is that modern varieties of marijuana (skunk, cheese) have a 20% THC content instead of a 1-10%.
If you’re finding your mental health is struggling, think about changing to the weaker strains of cannabis, smoking less often (with a vaporiser) but ideally abstaining altogether.
Sam Fitzpatrick Final Year Medical Student, Cardiff University.
Milad Rouf Final Year Medical Student, Cardiff University.
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