How cannabis affects mental illness

A full frame of marijuana foliage, background wallpaper

Most people consider marijuana a harmless drug. This assumption may have gained traction back in the 1960s or 1970s when marijuana’s effects were fairly mild—some giggling, getting the munchies and falling asleep. But today’s marijuana is a whole new ballgame.

The potency of the product is determined by the THC levels, the primary psychoactive ingredient in marijuana. In the 1970s, marijuana averaged 1.37 percent THC. In 2009, the product averaged 8.52 percent, a five-fold increase in potency. Some of the intensively cultivated domestic cannabis even has up to 22 percent THC content.

The increase in marijuana’s potency may explain the significant relationship between cannabis use and the onset of psychotic symptoms in some individuals. In a recent paper published in the Journal of Affective Disorders, researchers from Warwick Medical School sampled 2,391 study participants who had experienced mania symptoms.

Mania is part of bipolar disorder and includes feelings of persistent elation, hyperactivity, reduced need for sleep and increased energy. In addition, mania can cause the individual to feel aggressive and angry, and in some extreme cases, delusional.

“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,” said Dr. Steven Marwaha, the lead author of the study.

The results of the review suggest that marijuana use significantly worsened mania symptoms in people who had previously been diagnosed with bipolar disorder. Dr. Marwaha added, “cannabis use is a major clinical problem occurring early in the evolving course of bipolar disorder.”

Marijuana and the mind

Clinicians agree that cannabis use can cause acute adverse mental effects that mimic psychosis. There is an abundance of evidence to support this association, but the complex connection is not fully understood. In people with a genetic vulnerability toward mental illness, marijuana’s effects can trigger the development of a psychiatric illness. Studies have shown that as the frequency of marijuana use increases, the risk for developing a psychotic disorder also increases.

Cannabis use can lead to acute psychosis and cause serious symptoms of depersonalization, panic, paranoia, feelings of persecution, fear of dying and delusions. A study called the Epidemiologic Catchment Area (ECA) study found that 41 percent of patients with bipolar disorder engaged in co-occurring cannabis abuse. The study reported that cannabis abuse prior to development of bipolar disorder has a significant effect on first-episode mania and the ongoing course of the disease.

Dr. Allan Schwartz, Ph.D. is a psychiatrist with decades of experience in psychiatric hospitals working directly with patients who suffer from bipolar disorder, among other mental illnesses.  “I have directly witnessed the tragedy of patients going off of their medications for bipolar disorder, using marijuana and ending up re-hospitalized in worse shape than any time prior to the relapse,” Schwartz said. “It has been my experience with the patients I knew who suffered from severe bipolar disorder and with those who fell into the schizoaffective domain, that they were not helped by marijuana and were made much worse through its use.”

Again, the question is whether cannabis use causes mental illness among predisposed individuals or whether it exacerbates existing illnesses. In fact, in a general population of cannabis abusers, only a small percentage exposed to the drug develops a mental illness. But because there is an increase in the use of marijuana among the youth and a rise in schizophrenia in the younger population, there needs to be more studies about the potential harm of cannabis abuse.

White River Academy, places an emphasis on character development in adolescent males with behavioral issues, offering life skills classes and community service oriented programs to instill qualities that lead to a productive and successful life post-recovery. For questions about White River Academy and its treatment program for addiction, please call 866-520-0905.

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