From the University of Warwick located in the heart of England, adjacent to the city of Coventry, a research team set out to examine whether cannabis consumption made patients manic or if mania symptoms preceded pot use. In 2015, they published their disturbing findings in the Journal of Affective Disorders.

Lead author Dr Steven Marwaha said: Previously it has been unclear whether cannabis use predates manic episodes. We wanted to answer two questions — does cannabis use lead to increased occurrence of mania symptoms or manic episodes in individuals with pre-existing bipolar disorder? But also, does cannabis use increase the risk of onset of mania symptoms in those without pre-existing bipolar disorder?[ref]Cannabis use and mania symptoms: A systematic review and meta-analysis. Journal of Affective Disorders, 2015; 171: 39[/ref]

After searching through the available data from previous studies the researchers concluded that marijuana use preceded the onset of mania symptoms. Not only that but cannabis smoking worsened pre-existing mania symptoms in patients already diagnosed with bipolar disorder.

The observed tendency for cannabis use to precede or coincide with rather than follow mania symptoms, and the more specific association between cannabis use and new onset manic symptoms, suggests potential causal influences from cannabis use to the development of mania. It is a significant link.

….our review suggests that cannabis use is a major clinical problem occurring early in the evolving course of bipolar disorder.[ref]IBID[/ref]

There is a lack of investigational studies on cannabis and mania or bipolar disorder suggesting that this is a relatively neglected area of research the author said.

What we do know is that the associations of mania and cannabis use are so significant that the study team suggested there is a strong possibility that something in marijuana causes or worsens mania symptoms. From another study released this year (2015) in the Journal of Affective Disorders:

Studies support an association between cannabis use and the exacerbation of manic symptoms in those with previously diagnosed bipolar disorder. Furthermore, a meta-analysis of two studies suggests that cannabis use is associated with an approximately 3-fold… increased risk for the new onset of manic symptoms.[ref]IBID[/ref]


Studies have also shown that cannabis is the most commonly abused drug among those diagnosed with bipolar disorder.[ref]Psychiatry (Edgmont). 2009 Dec; 6(12): 44–48. Published online 2009 Dec.[/ref]

What follows is the case of a college student who initially suffered from an acute psychotic breakdown secondary to cannabis use that later manifested into a permanent diagnosis of bipolar disorder with psychosis.

Mr. X is a 21-year-old, African-American man who was brought to the Greater Binghamton Health Center (GBHC), Binghamton, New York, for exhibiting hostile and grandiose behavior. This was his second psychiatric hospitalization. He was discharged one week prior after a 30-day stay with a diagnosis of cannabis-induced psychotic disorder. After being discharged and having no overt psychotic symptoms, he started using cannabis again and became symptomatic with more pronounced delusions and psychotic behavior.

What makes this case interesting and special is that he had no known risk factors for psychosis. He was highly functional prior to admission maintaining a 3.3 GPA with a major in chemistry. Yet he became psychotic apparently after simply smoking cannabis. His toxicology screen was positive only for marijuana. The authors comment:

Several case studies and longitudinal studies have illustrated the link between acute psychosis and mania associated with cannabis (three citations). The most prominent symptoms elicited are auditory hallucinations, paranoid feelings of being persecuted, depersonalization, derealization, anxiety, grandiosity, irritability (four citations). The debate remains as to whether or not cannabis can cause schizophrenia and bipolar disorder in an otherwise healthy individual.[ref]IBID[/ref]

Questions that need addressing are what formulations of marijuana tend to aggravate mania symptoms? Is it the THC content? What about the potential effects using strains high in CBD and very low in THC like Charlotte’s Web? Perhaps these varietals will help attenuate manic symptoms. What about using pure CBD administered sublingually?

There is nothing currently in the literature that can help shed light on these and other unknowns. In order to know for sure placebo controlled, randomized, double-blinded studies need to be organized using human volunteers.

Based on these and other findings I would suggest that young people be very, very cautious before using cannabis for the first time-especially if you have ANY family history of psychiatric disease. The risk for developing “affective” disorders in otherwise normal people with no risk factors for mania or psychosis is small but possibly real. Use caution until we know for sure what’s happening at a biochemical and clinical level.

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