CBD for Depression: What the Science Says

By | Updated on December 13, 2023

Medically reviewed by
Kimberly Langdon

Evidence Based 32

Key takeaways:

  • Early research suggests that CBD has antidepressant effects.
  • More human studies of CBD’s antidepressant potential are needed.
  • While CBD is generally safe, large doses can interact with some drugs. For example, one study found that CBD increased the effects of the antidepressant citalopram. Consult your doctor before use if you’re taking any medications.

Cannabidiol (CBD), a non-intoxicating compound from cannabis, has grown popular for relieving anxiety and other issues. Many people also take CBD for depression (1).

Early evidence suggests that CBD may have antidepressant effects. But most of the data comes from studies of rats and mice, so proper human studies are needed.

Here’s how CBD might help with depression, the research evidence, dosage, side effects, and other evidence-based tips. 

What Does the Research Say?

High-quality research evidence for CBD’s antidepressant effects is lacking. But early findings are encouraging, with many researchers calling for proper clinical studies.

Human Studies

One 2022 study of 31 young people (aged 12-25) with treatment-resistant anxiety disorders found that CBD improved depressive symptoms (2).

Another 2018 study looked at using CBD to improve mood and other psychological symptoms associated with chronic cannabis use. Twenty frequent cannabis users took 200 mg CBD capsules daily for ten weeks, which improved depressive and psychotic symptoms (3). 

Meanwhile, a 2020 case report of a teenage boy with multiple substance use disorder, severe depression, social anxiety, and other issues found that CBD improved depressive and anxiety symptoms (4). 

He took pure CBD capsules for eight weeks, starting at 100 mg and moving up to 600 mg, after ineffective treatment with the antidepressant sertraline (Zoloft) for six months.

Additionally, a 2014 study found that Sativex, a drug that contains equal amounts of THC and CBD, improved irritability and depressive symptoms in 51 people suffering from cannabis withdrawal (5).

Although these findings are less relevant because CBD products contain relatively small amounts of THC, they still suggest some potential benefits. 

Finally, a 2021 academic book on depression summarized that “preclinical evidence suggests it [CBD] can be a promising new antidepressant” and called for further research (6). 

Animal Studies

Multiple studies of rats and mice have shown the antidepressant effects of CBD:

  • In a 2016 study of depressed rats, CBD improved anhedonia, the inability to feel pleasure (7)
  • In a 2019 study, a single dose of CBD had rapid antidepressant effects in mice (8)
  • In a similar 2019 study, CBD showed antidepressant effects in depressed rats (9)

CBD and Anxiety: An Important Link

Research suggests that depression often goes hand-in-hand with anxiety. One worldwide survey found that 45.7% of people with major depressive disorder — the medical name for depression — experienced one or more anxiety disorders during their lifetime (10).

Additionally, 41.6% of people with depression lasting 12 months had one or more anxiety disorders during the same time period. Data from another study also found that 53% of people with clinical depression experienced significant anxiety and were considered to have “anxious depression.”

The good news is that CBD has been shown to help with anxiety and specific anxiety disorders:

  • In a 2019 study of 37 Japanese teenagers (18-19 years old) with social anxiety disorder (SAD), CBD oil decreased anxiety (11)
  • In another 2019 study out of Colorado, CBD capsules lowered anxiety in people with anxiety and sleep issues (12)
  • In a 2011 Brazilian study, CBD capsules reduced anxiety caused by public speaking in people with SAD (13); similar results were reported by a 2019 study using the public speaking test in healthy adults (14)
  • A 2020 review paper that looked at many studies of CBD for anxiety concluded that ‘CBD has a promising role as alternative therapy in the management of anxiety disorders.” (15)
using cbd oil for depression

How Does CBD Help With Depression?

Although we don’t yet have a full picture, CBD may help with depression in several ways.

Most notably, multiple studies report that CBD’s antidepressant effects come from its interaction with serotonin 5-HT1a receptors in the brain (16, 17). Research suggests that this receptor is involved in anxiety, mood, depression, and other mental disorders (18). 

This isn’t surprising since serotonin is the same brain chemical targeted by selective serotonin reuptake inhibitors (SSRIs) — the most widely used type of antidepressant medication.

Another possible mechanism is CBD supporting adult neurogenesis, the formation of new neurons in the adult brain.

A 2022 study in rats showed that chronic stress impaired neurogenesis by encouraging neural stem cells to turn into different types of cells called astrocytes. When CBD was administered, it produced an antidepressant effect and prevented this abnormal cell differentiation (19).

There’s also growing evidence that our endocannabinoid system (ECS), which consists of endocannabinoids made by our bodies and the receptors they activate, is involved in depression (20). 

CBD can support ECS function by increasing the levels of anandamide, one of the two main endocannabinoids (21). Anandamide has been shown to have antidepressant effects in rats (22, 23).

A 2020 study in women with fibromyalgia also found that exercise increased anandamide levels and decreased pain and depression scores, suggesting a possible link (24).

Other potential ways CBD might help with depression include:

  • Increasing brain-derived neurotrophic factor (BDNF), a protein that promotes neuron growth, maturation, and maintenance (25, 26)
  • DNA methylation, histone modifications, and the regulation of miRNA expression (25)

How to Best Use CBD for Depression

If you’re looking for the strongest mood-boosting effects, we recommend opting for full-spectrum CBD oil.

Although you can also use gummies and capsules, they’re less effective because CBD has low oral bioavailability, which means only a small portion of what you take is absorbed by the body (27).

Meanwhile, if you’re looking for rapid relief, vaping CBD is another option. This administration route has high absorption and nearly instant effects (28).

Another key tip is to use full-spectrum CBD products instead of those containing pure CBD. Full-spectrum CBD is rich in all of hemp’s cannabinoids, terpenes, flavonoids, and other natural compounds, which work synergistically. 

Research suggests that full-spectrum CBD extracts may be as much as four times more effective than purified CBD (29).

It’s best to take CBD once or twice daily for depression, but you can also take it only when you need the relief.

cbd oil dropper

How Much CBD Should I Take?

There’s no one-size-fits-all CBD dose for depression. It depends on how much you weigh, your unique body chemistry, the severity of your symptoms, the type of product you’re taking, and other factors. 

The best approach is to start with a small amount and slowly raise it (30). You can begin with 10 mg or the CBD dose recommended by your product. Wait two hours to see the effects; if it’s not enough, gradually increase the dose until you feel the desired effects.

Follow this method to find the lowest effective dosage.

Are There Any Side Effects?

Research has shown that CBD is a generally safe, non-intoxicating substance. It has mostly minor side effects, such as: (31)

  • Tiredness/sleepiness
  • Diarrhea and nausea
  • Low blood pressure
  • Lightheadedness
  • Changes in weight or appetite
  • Dry mouth

Most of these effects were reported in studies using very high oral doses of pure CBD, so they’re less likely to happen for regular CBD users. 

Additionally, high doses of CBD may interact with some medications because it can affect enzymes that help your body metabolize drugs. Most notably, a 2021 study found that CBD significantly increased the concentrations of the SSRI antidepressant citalopram (Celexa) (32). 

As such, it’s important to consult a qualified healthcare professional before adding CBD to your regimen, especially if you’re already taking antidepressants. 

CBD: A Promising Alternative

Research suggests that CBD may have antidepressant effects. Although most of the evidence is limited to animal studies, early investigations of individuals with depressive symptoms have also shown promising results.

Still, high-quality clinical trials in people with depression are needed before we have strong proof. 

It’s not surprising to see many people turn to natural options like CBD over traditional SSRI antidepressants, which don’t work for everyone and can also cause a long list of significant side effects.

If you’re interested in trying CBD for depression, we recommend going with a top-notch full-spectrum CBD oil and experimenting with dosage until you start to notice positive effects.

References

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  2. Berger, Maximus, et al. “Cannabidiol for Treatment-Resistant Anxiety Disorders in Young People: An Open-Label Trial.” The Journal of Clinical Psychiatry 83.5 (2022): 42111.
  3. Solowij, Nadia, et al. “Therapeutic effects of prolonged cannabidiol treatment on psychological symptoms and cognitive function in regular cannabis users: a pragmatic open-label clinical trial.” Cannabis and cannabinoid research 3.1 (2018): 21-34.
  4. Laczkovics, Clarissa, et al. “Cannabidiol treatment in an adolescent with multiple substance abuse, social anxiety and depression.” neuropsychiatrie 35.1 (2021): 31-34.
  5. Allsop, David J., et al. “Nabiximols as an agonist replacement therapy during cannabis withdrawal: a randomized clinical trial.” JAMA psychiatry 71.3 (2014): 281-291.
  6. Joca, Samia, et al. “Putative effects of cannabidiol in depression and synaptic plasticity.” The Neuroscience of Depression (2021): 459-467.
  7. Shoval, Gal, et al. “Prohedonic effect of cannabidiol in a rat model of depression.” Neuropsychobiology 73.2 (2016): 123-129.
  8. Sales, Amanda J., et al. “Cannabidiol induces rapid and sustained antidepressant-like effects through increased BDNF signaling and synaptogenesis in the prefrontal cortex.” Molecular neurobiology 56.2 (2019): 1070-1081.
  9. Shbiro, Liat, et al. “Effects of cannabidiol in males and females in two different rat models of depression.” Physiology & behavior 201 (2019): 59-63.
  10. Kalin, Ned H. “The critical relationship between anxiety and depression.” American Journal of Psychiatry 177.5 (2020): 365-367.
  11. Masataka, Nobuo. “Anxiolytic effects of repeated cannabidiol treatment in teenagers with social anxiety disorders.” Frontiers in psychology (2019): 2466.
  12. Shannon, Scott, et al. “Cannabidiol in anxiety and sleep: a large case series.” The Permanente Journal 23 (2019).
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  18. Russo, Ethan B., et al. “Agonistic properties of cannabidiol at 5-HT1a receptors.” Neurochemical research 30.8 (2005): 1037-1043.
  19. Hou, Ming, et al. “Cannabidiol prevents depressive-like behaviors through the modulation of neural stem cell differentiation.” Frontiers of Medicine 16.2 (2022): 227-239.
  20. Gallego-Landin, Ines, et al. “Reviewing the Role of the Endocannabinoid System in the Pathophysiology of Depression.” Frontiers in pharmacology 12 (2021).
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