How does medical marijuana affect bipolar disorder?

Cannabis has received a ton of attention lately thanks to its ability to help ease the symptoms of mental conditions like depression and anxiety, both of which are usually associated with bipolar.

The National Institute of Mental Health estimates that 4.4% of US adults experience bipolar disorder, also known as manic-depressive disorder, at some point in their lives.

Bipolar disorder is a condition that causes extreme mood swings (ranging from states of extreme elevation to deep depression) and can be devastating, although many patients are able to control their mood and behavior with medication and healthy lifestyle habits.

So, what does the science say about cannabis and how it affects people with bipolar disorder?


The word “bipolar” refers to something that has two extremes. And, as the name suggests, people with bipolar disorder deal with a life that is split between two very different emotional states.

Bipolar disorder, like many other mental disorders, affects each patient differently. However, the most common types of bipolar disorder are:

Type 1: Characterized by periods of extreme elation (known as manic episodes) followed by periods of deep depression.

Type 2: Characterized by briefer, less extreme periods of elation followed by long periods of depression.

People with bipolar disorder struggle to maintain the emotional balance needed to lead a healthy, normal life. It’s also important to note that the highs of manic episodes greatly exceed regular feelings of joy. Instead, they usually bring with them a wide variety of negative symptoms, including:

  • Racing thoughts
  • Sleeplessness
  • Irritability
  • Rapid speech
  • Impulsive behavior
  • Risky behavior

Without treatment, manic episodes become more frequent, intense, and take longer to subside.

Depressive episodes, on the other hand, are the complete opposite, leaving a patient feeling drained, unmotivated, and hopeless. Symptoms of a depressive episode include:

  • Extreme sadness or feelings of hopelessness
  • Very low energy levels
  • Over or under-sleeping
  • Trouble finding joy in anything
  • Antisocial behavior
  • Changes in appetite
  • Suicidal thoughts

Notwithstanding, many patients are able to keep their condition in check with medication and therapy, which allow them to lead more or less regular lives.

For others, however, the condition can be all-encompassing, leading to performance issues at school or work, difficulties maintaining relationships, financial problems, and possible dangers to personal safety.

Bipolar disorder is also linked to other mental conditions. In fact, people with bipolar disorder also regularly experience:

  • Psychosis or display symptoms of psychosis, such as delusions and hallucinations
  • Anxiety and ADHD


The exact cause of bipolar isn’t known. However, research has shown that people with bipolar disorder exhibit some structural changes in the neural pathways of their brain.

In healthy individuals, the brain constantly “cleans” itself of faulty or unused neural connections. In turn, it stabilizes and strengthens its existing pathways.

Using functional resonance imaging, researchers have noticed that this “pruning” or cleaning ability of the brain is disrupted in people with bipolar disorder. Instead, their brains have a network of neural connections that are hard to navigate and control. These confusing neural signals are what cause the sporadic, abnormal thoughts and behaviors that characterize the condition.

Bipolar disorder also tends to run in families, suggesting that genetics play a big role in its development. Unlike other mental conditions, however, bipolar disorder isn’t related to a specific gene. Instead, researchers believe a number of genes are involved.


Today, bipolar disorder is treated with a combination of medication and lifestyle changes.

Common medications used to control the disorder are mood stabilizers like:

  • Carbamazepine (Carbatrol, Epitol, Equetro, Tegretol)
  • Divalproex sodium (Depakote)
  • Lamotrigine (Lamictal)
  • Lithium
  • Valproic acid (Depakene)

These medications help decrease abnormal brain activity and strengthen healthy neural connections and pathways.

Electroconvulsive therapy can also be used to control brain activity. This works by inducing a kind of controlled seizure in the brain via electric stimulation.

Regular exercise, healthy sleeping patterns, and abstinence from drugs and alcohol can also help control the behavior and emotions of bipolar patients.


Studies show that THC and CBD, as well as other compounds found in cannabis, may have beneficial effects for patients dealing with depression, anxiety, PTSD, etc.

Unfortunately, there still is a fairly limited body of research into cannabis and how it affects patients specifically with bipolar, but a 2015 study by researchers from Lancaster University, UK, served as a preliminary piece of research on the topic.

The study sampled 24 bipolar patients who used cannabis at least 3 times per week. The patients were asked to document how the use of cannabis affected their manic or depressive episodes in journal entries over 6 days.

The findings from the study were very inconclusive. Most of the participants used cannabis more for recreational purposes than medicinally. Some participants also noted that the effects of cannabis increased the symptoms of depressive or manic episodes.

However, the fact that cannabis can be beneficial for patients with depression and anxiety is also worth mentioning. For example, a variety of studies have shown that CBD can help patients calm symptoms of anxiety disorders. Research has also shown that small doses of cannabis can be effective for improving mood in depressed patients.

Another noteworthy study is a study from 1998. The study by Harvard professors Dr. Lester Grinspoon and James B. Bakalar found 5 cases in which bipolar patients benefited from cannabis. All of the patients found that medical marijuana helped them manage the extreme highs/lows of their manic or depressive episodes.

One of the patients, a 47-year-old woman, even said she found cannabis to be more effective than any other medication she'd tried. Reflecting on her experience with cannabis, she said:

“Suppose I am in a fit of manic rage — the most destructive behavior of all. A few puffs of this herb and I can be calm. My husband and I have both noticed this; it is quite dramatic. One minute out of control in a mad rage over a meaningless detail, seemingly in need of a straitjacket and somewhere, deep in my mind, asking myself why this is happening and why I can’t get a handle on my own emotions. Then, within a few minutes, the time it takes to smoke a few pinches — why, I could even, after a round of apologies, laugh at myself."

The partner of another patient also found cannabis helped his wife deal with her symptoms during manic or depressive episodes. He said, during his wife's manic episodes, cannabis helped her relax and sleep and slowed down her speech. During her depressive periods, cannabis can help make her more active, he said.

At the same time, THC can also induce feelings of anxiety and paranoia. And while it might boost your mood initially, some people also find that they experience depressive symptoms in the days after using the drug.


For now, there is simply too little solid research to make concrete conclusions about how cannabis may affect patients with bipolar. As a general rule of thumb, bipolar patients should refrain from using drugs and alcohol to help promote healthy thinking patterns and emotions.

Nonetheless, some patients refuse regular mood-stabilizing medications as they claim they dull their senses and creativity. For these patients, finding a natural alternative that doesn’t induce these side effects would be a huge step in the right direction, and may help them finally find a treatment that works.

Until we see better, more detailed research into this topic, patients with bipolar should probably focus on working with their doctors to achieve a mix of medication and healthy lifestyle changes to help them control their condition.

Note: We have taken the utmost care and precaution whilst writing this article. That being said, please take note of the fact that we are not medical professionals of any kind. is strictly a news and information website. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment.