Millions use cannabis worldwide, both recreationally and medically. New research, however, links temporary psychiatric symptoms and cannabis use, even for first time users. This suggests we should see the benefits and risks of cannabis use as a nuanced debate—one that depends in part on the active compounds in the particular cannabis used.
Temporary Psychiatric Symptoms
A recent research review and meta analysis found that a single dose of THC, the main psychoactive ingredient in cannabis, can induce symptoms in otherwise healthy people. The temporary psychiatric symptoms include paranoia and hallucinations—symptoms associated with schizophrenia.
“The first takeaway is that for people in general there is a risk, even if you are healthy and taking a single dose, a one-off, you could have these symptoms,” study senior author Oliver Howes told CNN. “They are distressing and could affect your thinking. You might not behave in a safe or rational way. It’s not just something that’s going to affect people with a history of mental health problems.”
So, genuine thought from a cannabis user: do you mean that it’s possible that you’ll feel paranoid and panicky? Or even hallucinate? Because this is known to the community.
Part of the difference in this study is that the authors are emphasizing the general risk for all users from even one use. An additional implied difference may be how severe these side effects are, and how commonly they occur.
The authors characterized psychiatric symptoms to include paranoia, including thinking others are talking about or threatening you somehow, and hallucinations such as hearing voices. (It is important to note that the authors clarify: having symptoms isn’t the same as having a psychiatric illness.)
CBD vs THC
Another difference is that the research found no evidence that cannabidiol (CBD) either induces or mediates psychiatric symptoms. CBD, a non-psychoactive cannabis compound that is used in some medicinal products, and THC are both found naturally in cannabis. However, while THC produces the classic “high” feeling cannabis is known for, many users believe CBD produces benefits without the euphoria. For example, some users have found CBD can help treat heroin addiction.
The researchers systematically reviewed 15 studies from clinical settings. The studies included 331 participants with no history of major psychiatric disorders, including psychotic disorders.
The team focused on healthy adults who were not at special risk for psychiatric disorders. This is in part because previous research established a connection between psychiatric symptoms and cannabis use, but not whether users with existing issues might be using cannabis to mitigate those problems.
And while the review indicated that CBD does not cause psychiatric symptoms, it also suggests that CBD might not temper the effects of THC as much as previously believed.
An additional preliminary finding in the review suggests that smokers are less sensitive to THC’s effects. This might be because tobacco somehow interacts with the THC receptors in the brain.
Study Takeaways
One important takeaway from the study is simply that, as with any new psychoactive medication, go slowly, especially as a new user. This is not new advice—although it may be new to the many new users that changing laws and norms are drawing to the scene.
In fact, laypeople have long understood the connection between using cannabis and the potential for feeling paranoid. Paranoia or panicky feelings are among the natural negative consequences of using cannabis—they can’t all be positive!—and the reason some people don’t enjoy using it.
The other important takeaway here is that more research will bring more medical utility and comfort to more people. Cannabis users and their healthcare providers alike will benefit from having the same levels of scientific evidence and number of clinical studies as other medicines do.