Decoding cannabis: Can UK medical cannabis help with depression this World Mental Health Day?

In mid-2024, researchers working at the Drug Research Institute in Budapest, Hungary released “Herbal Cannabis and Depression: A Review of Findings Published over the Last Three Years”. This fascinating review is a global analysis of 156 studies, and the findings are worth decoding.

What did the 2024 review reveal about medical cannabis for depression in the UK?

While the study didn't focus purely on UK findings, that doesn't make it any less applicable. Rates of depression have risen globally across the board, and so the findings of this review are very much worthy of discussion.

We will go into specifics further on in the blog (with the full findings explained), but the review shows a few key points quite clearly. 

• Firstly, the levels of THC and CBD in medical cannabis products seem to play a defining role in how effective they are when added to a holistic treatment plan for depression.

• And that medical cannabis treatment for depression should never be seen as a ‘one size fits all’ solution. The right cannabis-based treatment option depends on the patient and their individual response, their specific symptoms and health goals, with ongoing clinical guidance being absolutely key. 

Why are balanced THC and CBD ratios important in medical cannabis treatment for depression?

THC has been shown to offer great therapeutic potential for a really wide range of health issues, but when it comes to mental health, the findings are quite nuanced. 

The review in question found that many of the studies pointed to balanced THC:CBD formulations being the more effective options for depression symptom control than THC-dominant products.

Why?

Well, CBD appears to ‘soften’ the heavier psychoactive effects of THC, offering a steadier impact on mood and general emotional regulation. That is not to say the euphoric, often joyous lift that can be associated with THC is inherently negative, just that in patients with mental health issues, it needs to clinically guided, and that CBD’s moderating impact seems to help transform that lift from a proverbial rollercoaster rush into a more stable sense of wellbeing. 

How do cannabinoids influence serotonin and mood regulation in depression?

Central to our emotional landscape and general feelings of well-being are two neurotransmitters: serotonin and dopamine. They influence so much of how we feel, think, perceive, and interact with the world. They shape our mood, which leads to our emotional resilience and also motivation. 

The review highlights a few key studies here. 

CBD interacts with the 5-HT1A receptor system

Several papers have shown that there is a direct link between the activity of CBD and the 5-HT1A receptor system, which is one of the main serotonin pathways in our brains. When the 5-HTP1A receptor is activated, we feel higher levels of calm, focus, motivation, and emotional stability - all of which can be somewhat lacking in patients diagnosed with clinical depression. 

CBD enhances the activity of these receptors, and in turn, potentially helps the brain regulate our serotonin levels more efficiently. Fewer big dips, and also fewer big dumps. This goes a long way in explaining why CBD has shown such great promise across both animal and human trials as a mood stabiliser. 

Instead of forcing a huge surge of that feel-good neurotransmitter like certain stimulants do, CBD works more like a regulator. It helps to restore the natural cadence, the normal balance of serotonin in our brains, which can be extremely beneficial for people with depression. It doesn't force happiness or joy, but it creates the conditions where those feelings can naturally prosper. 

THC and its complex relationship with mood

As THC is an intoxicant, its effects on mood are far more complex than CBD, and also more individualised. While it does offer a definite mood and motivation boost for some patients, these can be short-lived, and the research points to it being dose-dependent. 

• At lower levels, it can help that feeling of emotional dullness associated with depression, and also improve focus.
• With higher doses, these effects can actually be reversed.

While not included in the review and focusing on anxiety rather than depression, “Effects of Marijuana on Mental Health: Anxiety Disorders” shows this biphasic effect quite clearly. Again, results are very individualised, which is why clinical guidance and oversight are so critical when it comes to medical cannabis treatment for all mental health disorders.  

But, when taken in conjunction with a balanced level of CBD to help even out the psychoactive effects of THC, the combo of these cannabinoids seems to contribute to a more even level of mood regulation and reduced levels of both anxiety and depression. 

Does medical cannabis act like an antidepressant for depression?

While medical cannabis treatment options and SSRIs (the main group of pharmaceutical antidepressants) both act on our serotonin pathways, they do so in quite different ways. 

The review states that while medical cannabis should not be viewed as a ‘direct antidepressant’, when prescribed responsibly, it can complement traditional pharmaceutical approaches. 

That said, there is a growing body of anecdotal evidence (including Releaf patient stories) that shows that, for some patients, medical cannabis alone can make a real, measurable difference. 

SSRI’s work by gradually increasing the amount of serotonin produced and made available. Cannabinoids work differently. They appear to influence how sensitive our receptors are to the available serotonin, almost finetuning how our brain responds rather than forcing serotonin levels up. 

And while this is quite a broad statement, we expect to see more specifically targeted research on specific cannabinoid ratios (including, but not limited to THC and CBD) and their impact on receptor pathways in the near future.

What does this mean for UK patients interested in medical cannabis for depression?

For UK patients searching for alternative/complementary treatment options for depression, the message from currently available evidence is one of balance, patience, and medical supervision. 

For the best results, medical cannabis should be prescribed alongside their current treatment options, and very carefully monitored by a mental health specialist clinician. If medical cannabis is suggested for a patient, the current research shows that a balanced THC/CBD product is the safest approach and offers the highest chance of consistent, ongoing improvements in mood, motivation, and general quality of life. 

Releaf patients have access to a world-class clinical team which includes specialists covering a huge range of health conditions, from psychiatric specialists to experts in chronic pain, neurology, oncology, gastroenterology, women's health concerns, and sleep disorders. This team of specialists is backed by GPs, nurses, and our 30+ team of UK-based Patient Support specialists.

As depression so often overlaps with other health issues (anxiety, sleep disturbances, chronic pain, hormonal changes, etc.), this breadth of expertise makes the Releaf patient experience genuinely holistic. Our clinical team consider every aspect of our patients' health before any decision is made regarding a potential medical cannabis prescription. 

Want to learn more about medical cannabis for depression in the UK?

Head to our medical cannabis eligibility checker. It costs nothing, takes just 20 seconds to run through, comes obligation-free, and may be your first steps to better health and a brighter future. 

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