High-potency marijuana strains, grown under precise laboratory conditions and sold legally, semi-legally, and illegally across the United States and Europe, can lead to an increased risk of psychoses, says a new study published in The Lancet Psychiatry.
As NPR News reports, the psychiatric community has known for decades that daily marijuana use, or too much marijuana use at one time, can lead to a psychotic episode — that is, when the patient loses touch with reality. But things are different now — with advances in growing techniques, as well as legalization in Canada and parts of the U.S., much of the cannabis available to the average user is considerably more potent than it was even a few decades ago.
Not your father’s marijuana
As High Times reports, back when “cannabis culture” started becoming a thing in the ’70s, even the best pot was largely grown outdoors, where growing conditions can’t be controlled as tightly and, even worse for the final product, growers risked accidentally having their plants fertilized, which ruins the THC content.
These days, the THC content of even basic strains at legal dispensaries is around 17 to 18 percent. Some strains can reach as high as 30 percent, and one Dutch strain, Nederhasj, can be as high as 67 percent. By comparison, in 2008 the average potency of pot sold in the U.S. was around 8.9 percent.
All of that THC — or tetrahydrocannabinol, the psychoactive ingredient in marijuana — isn’t necessarily good for the brain.
Researchers looked at psychiatric admissions of pot users across several European cities and one Brazilian city and found that users who consumed cannabis daily were three times more likely than a control group to be hospitalized for psychiatric reasons. And the use of “high-potency” pot, which is defined by the researchers as having a THC content of over 10 percent, almost doubled the risk of psychiatric hospitalization compared to someone who has never used.
However, Dr. Diana Martinez, a psychiatrist and addiction researcher at Columbia University, is quick to warn against drawing too many conclusions from the new research.
“You can’t say that cannabis causes psychosis. It’s simply not supported by the data.”
She notes that there is a wide-ranging host of factors that play a role in psychosis and its development, and they are not all fully understood.
The study’s lead author, Martha Di Forti, however, warns that pot users would do well to know that the potent strains they’re smoking should be treated with some caution.
“They need to know what to look for and ask for help, if they come across characteristics of a psychotic disorder.”