CBD and depression: current research

To mark World Depression Day, we look at current research on the relationship between cannabis, CBD and this mental illness. Please remember that this is an informative article and is not intended to prevent, diagnose or treat any disease or symptom. Speak to your doctor if you have any questions and before using CBD.

The relationship between cannabis and depression

Depression has increased exponentially in recent years. In the wake of the pandemic, depression and anxiety have become very common mental health conditions.

Recovering your mental health requires treatments that are generally hard to access, which has led people with depression to take an interest in potential treatments such as CBD or cannabidiol.

Defining depression

Before we dive into the use of CBD to alleviate depression, we need to understand a little more about what this condition is all about.

Depression is a disorder of emotions manifested by symptoms such as sadness, anxiety, irritability, lack of motivation, insomnia and suicidal thoughts (1).

Although 40% of people with depression or anxiety do not seek treatment (2), treatment may include psychiatric or psychological therapy that can be costly, or medication that usually has side effects and sometimes stops working.

Neurological origin of depression

The neurobiology of depression is related to the modulation of serotonin and noradrenaline in our brain. Generally, an imbalance in the systems of these neurotransmitters is what produces the symptoms of depression and anxiety (3).

Therapies such as cannabis for depression could be helpful, as they can stimulate the recovery of physiological balance or homeostasis in the brain (4).

Cannabis and depression: what is the link?

Long before science began to study the potential of cannabinoids in depression, cannabis has been used for decades to treat anxiety.

In clinical practice, one of the most commonly used treatments for depression is anxiolytics. So we might infer that, if the cannabis plant has helped with anxiety for years, perhaps it can also help in the treatment of depression. However, existing scientific studies point to the contrary.

Effects of THC on depression

The tetrahydrocannabinol (THC) present in the cannabis plant, when used with CBD, has not been shown to be effective in treating depression, and could even worsen the patient's course (5). On the other hand, CBD used on its own does appear to be a potential treatment for depressive disorders.

CBD-rich cannabis oil for depression and anxiety

Although there are several ongoing clinical studies evaluating the effectiveness of CBD oil for depression, scientific evidence indicates that cannabidiol can treat the symptoms of anxiety (6, 7, 8, 9), reduce compulsive behaviours (10) and alleviate sleep disturbances (11), which can be symptoms of depression.

Although human studies on the use of cannabidiol for depression are very limited, in animal studies CBD has been shown to have effects that are smaller than, but similar to, those of antidepressant drug therapy (12).

How could CBD help with depression?

The truth is, nobody knows exactly. Simply put, the effectiveness of cannabidiol in depressive disorders is still being studied. The results of years of research suggest that CBD may help with depression through its anxiolytic effect.

CBD's ability to reduce anxiety involves several mechanisms of action, but in general it is linked to the activation of 5-HT1A serotonin receptors, which could produce an effect that is smaller than, but similar to, that of commercial anxiolytics.

Treating depression

Diagnosis by a doctor, psychiatrist or psychologist is an essential condition before any treatment for depression.

Most people associate depressive symptoms with an emotional state, but in some cases the symptoms may be the sign of an organic disease or a side effect of a medicine. That is why it is so important to see a specialist doctor for a proper assessment.

What is the CBD dose for depression?

You may be wondering: so how do you take CBD for depression? Or how much CBD should I take for depression? Well, there is no established dose; remember that its potential benefit is still being researched. What we can do is tell you what the studies say so far.

For now, the consistent evidence suggesting that CBD is effective for depression comes from animal models. These animal models include unconventional routes of administration that are not practical for humans. The doses are also very different depending on whether acute or chronic models are used.

How is CBD oil used for depression?

In clinical trials, the CBD doses that have produced anxiolytic results also vary widely. However, the dose that stands out most for relieving depression-like behaviours was found in a study that used 200 mg of CBD a day for 10 weeks in regular cannabis users (13).

On the other hand, in people who do not use cannabis, anxiolytic effects have been reported with a single 400 mg dose of oil-based CBD (14), or a single 600 mg dose (9) of oil-based CBD.

And for chronic use, cannabidiol has been tested for 1 to 3 months to reduce anxiety and improve sleep disorders, at doses of 25 to 75 mg/day over 1 to 3 months (11).

Bear in mind that, according to the literature, chronic doses are more effective than a single dose (15).

Vaporising CBD for depression?

It has also been reported that vaporised CBD may help with emotional processing (16).

Using CBD and depression medication

Can I use CBD if I am taking medication for depression?

Some medicines used to treat depression (such as fluoxetine or Prozac) work by inhibiting serotonin reuptake; in other words, they help make more serotonin available to our neurons.

On the other hand, cannabidiol, although it does not increase the amount of serotonin available, can stimulate its receptors and produce an effect similar to that of this neurotransmitter.

Interaction between CBD and selective serotonin reuptake inhibitors (SSRIs)

It has been observed that small doses of treatments such as fluoxetine that do not produce a therapeutic effect, when given with low doses of CBD that do not produce a therapeutic effect either, may have a synergistic effect when administered simultaneously.

This suggests that very low doses of cannabidiol and fluoxetine, when given together, may enhance an antidepressant effect (17).

As fluoxetine is a selective serotonin reuptake inhibitor (SSRI), the effect might also be seen with other medicines in this category, such as citalopram (Celexa), escitalopram (Lexapro), paroxetine (Paxil, Pexeva) and sertraline (Zoloft).

Remember that the combinations above have not been explored in clinical detail, and that the combination with fluoxetine was evaluated in a study carried out under laboratory conditions. Read our post on CBD and drug interactions to find out what happens when CBD is taken with another medicine.

Important note on using CBD for depression

Depression is a mental health disorder, and its treatment should be discussed with a specialist doctor. The approach will probably need to include different treatments, including psychotherapy. Consult your doctor before using cannabidiol for depression and other mental health disorders.

All medicines that act on the central nervous system, such as anxiolytics or antidepressants, must be carefully monitored by a healthcare professional.

Although studies suggest that CBD has the potential to treat some symptoms of depression, its use in treating depression is still being researched.

Please remember that this is an informative article that is not intended to prevent, diagnose or treat any disease. Consult your doctor before using CBD. Its content may complement, but never replace, the diagnosis or treatment of any disease or symptom. Cannactiva products are not medicines. We recommend that you consult your doctor if you are already receiving treatment for depression and that you do not use CBD without their advice and supervision.