Health & Medicine

This Is How Cannabis Affects People With Bipolar Disorder: Study

Kathleen Lees
First Posted: Mar 13, 2015 05:44 PM EDT

A new study on the effects of cannabis and Bipolar Disorder studies potential links to increases in manic and depressive symptoms.

The study, published in the journal PLOS ONE, was conducted by Dr. Elizabeth Tyler of the Spectrum Centre for Mental Health Research at Lancaster University, along with Professor Steven Jones and colleagues from the University of Manchester, Professor Christine Barrowclough, Nancy Black and Lesley-Anne Carter.

As it stands, statistics show that about 2 percent of the UK population has Bipolar Disorder, while close to 60 percent uses cannabis at some point in their lives. However, research is rather limited on reasons for high level use. (Statistics in the United States are relatively similar.)

"One theory that is used to explain high levels of drug use is that people use cannabis to self-medicate their symptoms of bipolar disorder," Tyler said, in a news release

For the study, researchers looked at people who had been diagnosed with bipolar disorder but who were not experiencing a depressive or manic episode during the six days the research was carried out.

Each of the participants completed a paper diary regarding their emotional state and drug use at several random points daily throughout the period of a week, which enabled many to log their daily experiences right in the moment.

"I do smoke a small amount to lift my mood and make myself slightly manic but it also lifts my mood and switches me into a different mind-set," said one of the participants. "I do not use weed to manage depression as it can make it worse, making me anxious and paranoid."

"I have found though that if I have smoked more excessively it can make me feel depressed for days afterwards."

Researchers came to the conclusion that cannabis use increased when individuals were in a good mood and was more typically associated with a more positive mood. On the other hand, cannabis use was also associated with an increase in positive mood, manic symptoms and paradoxically an increase in depressive symptoms, but not in the same individuals.

"The findings suggest that cannabis is not being used to self-medicate small changes in symptoms within the context of daily life. However, cannabis use itself may be associated with both positive and negative emotional states. We need to find out whether these relationships play out in the longer term as this may have an impact on a person's course of bipolar disorder."

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