Marijuana: Reefer Madness

Psychosis Risks with Marijuana Use


This article is taken from Bipolar Network News.

“At a recent conference Robin Murray, a researcher based in London, gave a talk about the potential adverse effects of tetrahydrocanabinol (THC). Considerable data indicate that chronic long-term smoking of marijuana is associated with the doubling of the risk of psychosis. Moreover, if a marijuana user has a common genetic variant in the catechol-o-methyltransferase enzyme (COMT), they are at substantially increased risk for the development of psychosis. New data also indicate that frequent use of marijuana can also be associated with an earlier onset of schizophrenic psychosis than would ordinarily occur without the substance use. Data also suggest that the psychosis associated with THC use is more difficult to treat than that without such use.

Murray also reported on a new risk that is associated with more potent new products. Older, natural forms of marijuana contained a compound called cannabidiol, which is associated with calming effects and possible antipsychotic effects. In a new synthetic preparation of THC called skank or spice, there is a higher amount of THC, but none of the positive diol compound. Thus there are some important caveats to the prevailing view that marijuana is relatively harmless.”

This is a much more sophisticated analysis than previous information about marijuana and its risks.

Our own experience is that marijuana can not only increase the risk of psychosis but also may over time lead to more rapid cycling in folks with bipolar. Also marijuana has clear effects on memory and attention span when used long term.

On the other hand, we know plenty of people without bipolar who find marijuana helpful for reducing anxiety and for managing pain. Our caveat is this – marijuana, like many psychoactive agents, has immediate or short term effects (reduction in anxiety for example) that may be quite different from its long term effects.