Can medical cannabis help ease the symptoms of depression? 

Depression is a debilitating condition that affects about 280 million people around the world. Subjecting patients to what is often described as overwhelming emotional numbness, extreme sadness, or all-consuming hopelessness, depression is a mental health condition that can impact a person’s emotional, physical, and social well-being.

People living with depression typically experience feelings of anxiety, disrupted sleep and eating patterns, as well as a lack of energy and motivation. Fortunately, there are several treatment options available to manage these symptoms, including medical cannabis for depression.

Typically, patients will receive a prescription for antidepressants from their GP or take part in different types of talking therapies (like CBT) with a counsellor. However, in some cases, these conventional options may not be appropriate or particularly effective, and around 1 in 3 people with mood dysregulation disorders build up a resistance to conventional antidepressants.

In 2023 a cross-national analysis of the UK, US, Canada, Israel, and Australia showed that depression was one of the major motivators for medical cannabis administration and around one third of patients suffering from chronic, serious, or life-changing conditions are thought to experience symptoms of depression.

In this article, we aim to explain the evidence available surrounding the application of medical cannabis in depression symptom management, including its short term effects and potential benefits, as well as the possible risks associated with taking medical cannabis. 

Does cannabis help with depression?

In 2019, it was found that around 8.3% of those diagnosed, or 653,456 people living with depression in the UK were thought to be taking illegally sourced cannabis to manage the symptoms of depression, or relieve the side effects caused by prescribed treatments.

In the same year, over a third (34%) of the registered medical cannabis patients in the UK were accessing cannabis-based medicines for the same reasons, and so, the prevalence of managing depression through the administration of medical cannabis is clear. But how does it actually work?

When cannabis-based products are taken, their cannabinoid contents enter the body. As they come from the cannabis plant, cannabinoids like THC and CBD are classed as phytocannabinoids, and when they are administered, they have the ability to mimic the cannabinoids that are naturally produced by the human body, called endocannabinoids.

Endocannabinoids can be classed as neurotransmitters because they carry messages around the body to regulate a range of functions including mood, memory, and metabolism. By interacting with receptors in and around the endocannabinoid system (ECS), endocannabinoids like AEA and 2-AG deliver these messages to elicit biological responses.

When phytocannabinoids (such as THC and CBD) are consumed, they can adopt a similar ability, and can influence and interact with a number of these endocannabinoid processes and pathways – including the body’s regulation of ‘happy hormones’, namely dopamine and serotonin.

The results from a Chinese study conducted in 2021 suggest that CBD administration can cause similar effects to those of commonly prescribed antidepressants. This was shown in significant increases in serotonin levels, a neurotransmitter that is associated with long-term happiness. 

Scientists have also discovered that THC stimulates the release of one of the body’s ‘feel good’ chemicals called dopamine, which improves overall mood and level of motivation. 

These findings indicate that certain cannabis compounds have the potential to combat some of the symptoms typically experienced by patients with depression, and could therefore be a viable treatment option in some instances. 

Pros of using cannabis-based treatments to manage depression

Recently, in 2022 a group of researchers in the UK began to study data from the UK’s largest medical cannabis registry, to assess the efficacy of medical cannabis using the patient health questionnaire scores given by patients with depression. 

After starting treatment with cannabis-based medicines, the baseline scores of these 129 patients improved at one, three, and six-month follow-up tests, moving many patients from the ‘moderate’ to the ‘mild’ category. Depression, sleep, anxiety, and quality of life scores were all seen to improve, and the medical cannabis treatment options were "generally well tolerated", with 87% of the adverse effects experienced by those taking part described as mild or moderate. 

This strengthens findings that have been gradually accumulating over the course of several years.

In 2010, an American research team analysed which components within the cannabis plant display antidepressant-like effects using mice as their test subjects. This study found that both major cannabinoids, THC and CBD, displayed antidepressant-like effects at extremely different dosages, whilst minor cannabinoids like CBN and CBG had little effects. The antidepressant-like effects were noted after just 2.5 mg of THC per kilogram of body weight was administered, versus 200 mg of CBD per kilogram of body weight. 

Two years later in 2012 the results from another American study involving patients with Bipolar disorder, which was formerly known as manic depression, found that medical cannabis could potentially benefit patients with this condition. In this study, patients with Bipolar disorder reported a significant mood improvement when consuming medical cannabis compared to the control group who did not consume cannabis, and compared to those without a Bipolar diagnosis who consumed cannabis for recreational purposes. 

Cons of using cannabis-based treatments to manage depression

Although there have been a number of clinical trials and observational studies that have demonstrated success in treating symptoms of depression using medicinal cannabis or cannabis-based medicines, there have also been a number of studies that demonstrate, this form of medication, like many others, is not suitable for everyone.

For example, it would be unwise to think that the common co-occurrence of major depressive disorders and cannabis use disorder is merely coincidental. Although many have logically theorised that overuse of cannabis or chronic cannabis consumption could potentially lead to major depressive disorders, researchers from a co-morbidity study in 2017 suggest this is only the case when the risk for cannabis use disorder is already high.

This implies those with a higher risk of addiction may not be appropriate candidates for cannabis-based treatments, or they may need to be monitored closely by their clinical time to ensure safety. Similar findings have been reported when analysing the relationship between cannabis and the risk of developing or experiencing psychosis, and so, those who are predisposed are generally advised against consuming cannabis. 

A Canadian study from 2020 also indicates that medical cannabis may not be as effective in patients who have mild, or less severe symptoms of depression. By observing patient health questionnaire scores given by registered patients using medical cannabis to treat a range of illnesses and conditions, only 3.4% were seen to have improved depression scored over three years and 1.5% reported a worsening of symptoms. 

Conclusion

Due to a large number of variables, a sweeping, generalised endorsement for the application of medical cannabis to treat depression cannot be made and clinical research in this area is limited. Thankfully, with the current state of global affairs regarding medical cannabis, the stigma surrounding cannabis-based treatments is slowly subsiding, and the access that is afforded to clinical researchers is ever-increasing.

It is also important to note that depression can be a complex and multifaceted condition, with various underlying causes and contributing factors. Personal biological factors, such as comorbidity and genetic characteristics, as well as variables within the formulation, concentration, and dosages of medical cannabis products all influence the effects of cannabis in patients with depression. 

The short-term effects, long-term effects, and potential benefits of taking medical cannabis for depression management vary from person to person. With this in mind, it should come as anything but a surprise that it is essential to seek out personalised advice from your clinician if you are considering medical cannabis treatment options to manage depression symptoms, and to never make any changes to your current treatment plan without discussing them with your doctors first.

At Releaf, we believe that access to medical cannabis is important. That's why we offer tailored monthly packages based on your cannabis prescription, specialist consultations for medical cannabis, and a unique medical cannabis card for protection.