Marijuana and Depression

Heavy marijuana use appears to be associated with depression, but studies haven’t found a clear link. We don’t know if people who are depressed are more likely to use marijuana. We also don’t know if marijuana can cause depression.
Topics On this page
| | 17 sources

It’s unknown if marijuana causes depression. It also isn’t clear if people who smoke weed are more likely to develop depression. Well-designed studies have resulted in conflicting evidence, so further investigation is needed.

Overall, infrequent marijuana smokers appear to have little to no risk of depression directly related to use of the drug. Heavy smokers may be at some risk.

Researchers have searched for ways that marijuana could cause depression in the brain. But they’ve been unable to find a biological cause.

Marijuana may indirectly influence risk of depression. For example, pot is linked to thinking problems, lower academic success and increased risk of other drug use. It’s also associated with injuries, problems at work and marijuana addiction. These factors may increase the chance of developing depression.

No evidence exists indicating that marijuana is an effective treatment for depression. The results of some studies suggest that people who are depressed shouldn’t consume marijuana.

Does Marijuana Cause Depression?

Dozens of studies have explored a possible link between depression and marijuana use. These studies have produced inconclusive or varying results. They examined different age groups, methods of use, rates of use and lengths of use. These diverse variables make comparing results difficult.

To try to make sense of the research, three meta-analyses on marijuana and depression have been conducted since 2003. A meta-analysis is a review of all research on a topic.

The three analyses on marijuana and depression reached similar conclusions:

  • In general, marijuana was associated with mental health problems.
  • Rates of depression were higher for people who frequently smoked marijuana than for the general population.
  • People who frequently used marijuana had a higher risk of depression than people who used it occasionally.
  • Some evidence suggested early marijuana use led to depression later in life. Other studies found no association.
Sources: Degenhardt, L., Hall, W. & Lynskey, M. (2003), Moore, T.H.M. et al. (2007), Lev-Ran, S. et al. (2014).

A 2016 large-scale study surveyed a national sample of adults between 2001 and 2005. The researchers found no association between marijuana use and depression. The study was funded by the National Institutes of Health and published in JAMA Psychiatry.

The largest study ever conducted on the health effects of cannabis was released in 2017 by the National Academies of Sciences, Engineering, and Medicine. It concluded that there was a small likelihood that marijuana use increased the risk of depression.

Can Marijuana Treat Depression?

Marijuana can cause a short-term sense of euphoria, but current research does not indicate it is an effective treatment for depression.

The National Academies study analyzed the use of cannabis for treating numerous health conditions, including depression.

It concluded that:

  • Moderate evidence suggested depression may increase the risk of marijuana use problems.
  • Limited evidence suggested marijuana was ineffective for reducing depression symptoms in people with chronic pain or multiple sclerosis.
  • Limited evidence suggested childhood depression was a risk factor for future marijuana problems.
  • No evidence suggested marijuana will improve or worsen pre-existing depression.

The finding that people with depression may be at risk for future marijuana problems should caution people from using the drug to treat depressive symptoms.

A 2017 study published in the Journal of Affective Disorders found that marijuana use was common among people seeking outpatient treatment for depression. It concluded that marijuana use was associated with poor recovery outcomes for people seeking outpatient treatment for the mood disorder.

Mixing Marijuana with Antidepressants

Little research has been conducted on the interactions between marijuana and antidepressants. Some side effects of antidepressants are similar to side effects of marijuana.

For example, marijuana and certain types of antidepressants can each affect heartrate, blood pressure, cognition and mood. Combining the drugs may make these side effects worse.

Tricyclics and Marijuana

A 2010 review found only one study on youth marijuana and antidepressant use. That study included case reports of four teens. The teens, who were taking tricyclic antidepressants, experienced cognitive changes, delirium and rapid heartrate after smoking marijuana. No studies have attempted to verify these effects.

Tricyclics are older antidepressants, such as amitriptyline, amoxapine, imipramine and trimipramine. Selective serotonin reuptake inhibitors, also known as SSRIs, are more commonly prescribed today.

Pot and Prozac

A case study of a woman who mixed marijuana with Prozac (fluoxetine), an SSRI, was published in The Journal of Clinical Psychiatry. The woman experienced severe mania and psychosis. No other similar cases have been reported.

Wellbutrin and Weed

Wellbutrin (bupropion) is an antidepressant that’s also prescribed to help people stop smoking tobacco. Researchers have studied whether Wellbutrin can help people stop smoking marijuana.

During these studies, people who smoked marijuana while taking Wellbutrin did not exhibit major changes to behavior. The authors concluded the antidepressant did not show promise as a treatment for marijuana dependence.

People with depression should speak to their health care provider about effective treatments. No studies have shown that marijuana effectively treats the mood disorder. Some research shows that those with depression are more likely to experience problems with the drug.

Marijuana can cause long-term health problems, including difficulty learning, paranoia and a condition called cannabinoid hyperemesis syndrome. Additionally, smoking marijuana can harm the lungs. Doctors can recommend safer ways to treat depression or help you stop smoking weed if you think it’s affecting your mood.

Medical Disclaimer: aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.

Chris Elkins, MA
Senior Content Writer,
Chris Elkins worked as a journalist for three years and was published by multiple newspapers and online publications. Since 2015, he’s written about health-related topics, interviewed addiction experts and authored stories of recovery. Chris has a master’s degree in strategic communication and a graduate certificate in health communication.

Was this article helpful?

How helpful would you rate this article?

    loading logo

    Thanks for helping us make our website better for visitors like you!

    View Sources

    Ready to make a change?

    Get cost-effective, quality addiction care that truly works.

    Start Your Recovery
    We're here to help you or your loved one.
    Question mark symbol icon

    Who am I calling?

    Calls will be answered by a qualified admissions representative with Advanced Recovery Systems (ARS), the owners of We look forward to helping you!

    Question mark symbol icon

    Who am I calling?

    Phone calls to treatment center listings not associated with ARS will go directly to those centers. and ARS are not responsible for those calls.