Every day after work, Tim*, a 27-year-old New York City-based nonprofit professional, does the same thing to deal with the anxiety he has struggled with since childhood.
As soon as he gets out of the subway, he takes out a joint kept tucked away in a smell-proof container in his backpack, lights it, and puffs while walking to his Queens apartment.
“I wouldn’t say it cures my anxiety, but it helps manage it,” Tim said. “It just kind of keeps me level.”
Many Americans like Tim smoke, vape or otherwise consume cannabis to take the edge off after a stressful day or to cope with anxiety, one of the most common mental health concerns in the United States.
But while marijuana can reduce anxiety in some people, it can exacerbate it in others — especially if the drug is highly potent.
Researchers don’t yet fully understand whether marijuana reduces or causes anxiety.
“In terms of anxiety the bottom line is that there is just a lot more that we have to learn about it,” said Devan Kansagar, professor of general internal medicine at Oregon Health & Science University School of Medicine. “We really don’t know.”
But a range of variables have been identified that determine how cannabis makes people feel in the short term.
For one, a person’s mental health state prior to consuming the drug can impact whether they feel anxious after taking it, as research shows cannabis can intensify emotions a user is already feeling.
Sex may also be a factor. Among infrequent cannabis users, women are more likely to feel anxious, nervous or restless after using the drug, according to one 2020 study.
“A person’s sex potentially influences every aspect of cannabis use,” said Esther Choo, professor of emergency medicine at the Oregon Health & Science University School of Medicine. For that reason, she said, “sex differences would not be surprising.”
But she cautioned that “the science is not consistent on what those differences are. The medical literature provides no clear basis to assume, for example, that women are consistently more prone to feeling intense or negative symptoms, like anxiety, from cannabis use versus men.”
The type of cannabis being consumed does play a significant role, mainly because different strains have varying concentrations of tetrahydrocannabinol (THC), the major psychoactive ingredient in marijuana.
“If you look at one of these rigorous studies where you’re comparing an active ingredient in cannabis to a placebo and looking at anxiety, what you see is that at a certain dose, participants will show decreases in anxiety compared to a placebo,” said Ziva Cooper, director of the UCLA Center for Cannabis and Cannabinoids.
“But when you get to a higher dose, people actually report more anxiety compared to a placebo.”
How people consume cannabis plays a role in whether the drug eases or worsens anxiety as well.
THC enters the bloodstream and reaches the brain much more quickly when a person smokes or vapes marijuana than when they eat a weed gummy or pot brownie.
And once THC gets to the brain, the chemical attaches to molecules called cannabinoid receptors on neurons, which changes the normal flow of communication within the brain and body and results in a high.
Inhaling cannabis smoke can cause a person to feel that high within a few minutes, while THC doesn’t fully take effect until 30 minutes to an hour after eating a marijuana-infused food or beverage, according to the National Institute on Drug Abuse.
“In some situations, someone may use an oral product, like an edible, not realize that it takes a little while to feel an effect and take more thinking they did not take enough,” Cooper said in an email. “This can lead to a situation where the individual is exposed to high amounts of THC, which may increase the chances of feeling uncomfortable, impaired, intoxicated, and anxious.”
Cannabis is a complex plant with over 100 different cannabinoid compounds, according to the Centers for Disease Control and Prevention. THC is just one of them. And the combination of these compounds in the cannabis a person is consuming can also impact how anxious they feel while using it, Cooper said.
Another cannabis compound is cannabidiol, or CBD, which is found in the cannabis sativa plant. Like THC, CBD is a psychoactive compound, or one that affects the mind, but it is non-intoxicating, meaning that while it possibly has a calming effect it does not cause a high in the way THC does.
One study found that CBD actually prevents THC and other cannabinoids from binding to certain receptors in the brain, reducing THC’s affect on a person’s mind or mood.
And there is a growing body of preclinical research that supports CBD’s potential to treat anxiety disorders.
But while cannabis could prove to be a treatment for anxiety in the future, some experts emphasize that just using the drug, or any other anti-anxiety medication, is only a short-term solution.
Beatriz Carlini, an associate professor at the University of Washington, told The Hill that cognitive behavioral therapy or mindfulness-based therapies can provide more long-term help for those struggling with anxiety.
* Name has been changed for the purpose of anonymity