People with bipolar disorder abuse marijuana more than any other drug. Some are trying to self-medicate their bipolar symptoms. Medical marijuana isn’t an approved method for treating bipolar disorder in states where medical cannabis is legal. The combination of marijuana and bipolar disorder can make an already difficult mental illness worse. Research shows about 70% of people with bipolar disorder use marijuana. Around 30% of those people meet the diagnostic criteria for cannabis use disorder. Some studies suggest the effects of marijuana abuse may even lead to bipolar symptoms.
The effects of marijuana and bipolar disorder can contribute to several complications:
Worsened Mood Issues and Psychosis
Cannabis can intensify the depressive or manic episodes of bipolar disorder. Marijuana acts on some of the same brain chemicals and functions that play a role in psychotic symptoms. These include dopamine, gamma aminobutyric acid (GABA) and glutamate transmission. Some researchers believe this is how cannabis abuse worsens or causes new bipolar symptoms. They recommend it not be used to treat bipolar disorder.
A meta-analysis of several studies on marijuana and bipolar disorder confirms cannabis use in bipolar disorder worsens symptoms of the mental illness. Marijuana use may increase the risk of new manic symptoms by as much as three times in people with bipolar disorder. Other research by the University of Manchester shows an increase in both manic episodes and depressive episodes. Study participants saw a 17% increase in bipolar depression symptoms. They also saw a 20% increase in manic symptoms after using marijuana.
Causes Faster and More Frequent Bipolar Symptoms
Bipolar disorder is marked by a “cycling” between extreme moods of depression and mania. Things like brain chemical fluctuations and people’s biological make-up contribute to the onset of these cycles. Cannabis abuse may lead to “rapid cycling” in people with bipolar disorder. Rapid cycling in bipolar disorder is four or more distinct affective states (i.e., depression or manic episodes) within a one-year period. One study followed 144 people with bipolar I disorder. The researchers found that people with bipolar who used cannabis experienced more cycling than those who didn’t use cannabis.
Increases Risk of Co-Occurring Disorders
Effects of marijuana and bipolar disorder increases the risk for other co-occurring behavioral health issues. One study examined data from a national survey on substance abuse and related conditions. Over 1,900 people with bipolar disorder and cannabis use disorder were represented in the sample. The researchers found marijuana and bipolar disorder can significantly increase the risk for:
- Alcohol dependence
- Drug addiction
- Antisocial personality disorder
- Nicotine dependence
Triggers Bipolar Symptoms in People With Certain Genes
There could be such a thing as cannabis-induced bipolar disorder. Research shows marijuana abuse may trigger psychotic conditions like bipolar disorder and schizophrenia in people with certain genes. Specifically, cannabis abusers with a variation of the AKT1 gene are at increased risk for psychotic disorders. The AKT1 gene is involved in dopamine signaling in the brain. Systems that regulate dopamine are thought to play a role in bipolar disorder symptoms. Cannabis users with this gene variation who smoke marijuana daily are seven times more likely to develop psychosis than people who don’t use cannabis. Moderate marijuana users are two times more likely to develop psychosis.
Increases the Risk of Suicide
Marijuana and bipolar disorder can be a deadly mix. People with bipolar disorder are at a heightened risk for suicide already. Cannabis use may further increase this risk. Depressive episodes can feel bleak in people with the disorder. The extreme highs and lows can be exhausting and debilitating. Abuse of drugs like marijuana may add to depression and hopelessness. Treating bipolar disorder with medical marijuana can be dangerous. A 2015 study published in Neural Plasticity found 42% of bipolar study participants who used marijuana had attempted suicide.
Makes Treatment More Complex
Bipolar disorder is a complicated disease with various biological and environmental components. Getting the right dose of mood stabilizers and finding which behavioral therapies work best for each individual is complex. Cannabis abuse makes this treatment challenge even more difficult. One study followed people with bipolar disorder who used cannabis over one year of dual diagnosis treatment. Compared to non-cannabis users they had:
- Less adherence to treatment plans
- More severe mania and psychosis
- Less overall life satisfaction
These are symptoms that typically improve in bipolar patients receiving treatment who aren’t abusing marijuana.
A Silver Lining
The good news is that many people with a bipolar diagnosis do get better. Using marijuana for bipolar disorder is not the answer though. Medical cannabis can dull symptoms for a while, but usually backfires. Bipolar is a lifelong illness. Patients with bipolar disorder require specialized bipolar treatment. It’s possible to improve symptoms with prescription drugs, behavioral therapy and a healthy lifestyle that doesn’t include substance abuse. Like all psychiatric disorders, managing mental health conditions is key.