Can Smoking Weed Protect Against COVID-19? Not Exactly

A recent study found that certain molecules in cannabis protect against COVID-19. And some corners of the internet are celebrating. Some late-night hosts are, too.

But the data is not so clear-cut. Although medical cannabis can offer users relief, there is no evidence to suggest that smoking weed protects people from COVID-19 infection.

Rather, two compounds not usually found in cannabis products humans use—cannabigerolic acid (CBGA) and cannabidiolic acid (CBDA)—were the stars of this research.

“CBDA and the CBGA, which we found to be active in our study, are heat-sensitive,” Richard van Breemen, PhD, professor of pharmaceutical sciences at Oregon State University and lead study author, told Verywell. “They decompose into other cannabinoids when exposed to heat sources, like what would occur in smoking.”

So, by the time someone has smoked the plant, these helpful cannabinoids are long gone. The study was published in the Journal of Natural Products in January.

Cannabinoids and COVID-19 Protection

Upon quick glance, the study seems to say that if you use cannabis, you might be more protected from COVID-19. But van Breemen explained why that’s not the case.

It all comes down to the spike protein on COVID-19. “That spikey projection you see on a picture of the virus,” he said. “It’s the spike protein that interacts with the human cell and begins infection.”

To prevent infection, antibodies latch onto the spike protein, thereby blocking its ability to enter human cells.

Knowing this, van Breemen and colleagues hypothesized that small molecules—perhaps from botanical dietary supplements including cannabinoids—could also bind to that spike protein. “If they interacted at the right place with the right binding affinity, they could also prevent that interaction between the spike protein in the human cell, and thereby prevent infection,” he said.

That’s exactly what happened. Researchers tested whether CBGA and CBDA could, in a petri dish with human cells, protect against COVID-19. In short, they found that the two compounds prevented entry of the virus into cells, stopping contagion in its tracks.

Importantly, CBGA and CBDA are not commonly found in commercial cannabis products. They’re found in the raw plant and are chemical precursors to the more well-known cannabinoids such as CBD and THC. Once the plant is heated and dried for products like weed, brownies, or gummies, these acids are converted into CBD and THC.

Cannabinoids and COVID-19 Risk

If CBGA and CBDA do protect against COVID-19, one thing still remains unclear: whether they’ll work in people. Watching cannabinoids inactivate COVID-19 in a petri dish is not the same as watching them do it in a human body.

The effects of smoking on the human body, however, are well-documented. Cannabis use disorder and smoking cannabis have repeatedly been linked to COVID-19 risk during the pandemic. This may be due to smoking’s irritation of the throat and lungs, its impact on the immune system, the likeliness of cannabis users to share with others, or exposure to toxic substances (like tar) that have been associated with the development of several conditions.

This is not to say that cannabis is all bad. Humans have been using it for millennia—and it’s becoming legal now in more places for its health benefits, including treatment of pain, epilepsy, and opioid detoxification.

The best thing to do is to talk to a doctor or health expert if you’re considering starting or continuing using.

Is CBD a Potential Treatment?

This is not the first study to suggest cannabinoids might work as a therapy for COVID-19.

CBD is already known for its anti-inflammatory and antioxidant effects on the human body. Then, in January 2021, researchers published further evidence that cannabis compounds reduced lung inflammation—a major complication that can be brought on by COVID-19.

Now, in January 2022, another study found that CBD disrupted COVID-19 infection, but in a different way than CBGA and CBDA. Rather than affect the virus’s ability to enter the cell, CBD blocked virus replication, which interfered with the virus’s ability to spread throughout the body.

And this CBD effect wasn’t just observed in a petri dish; it also inhibited virus replication in mice. What’s more, the authors found that people who use CBD on a regular basis caught COVID-19 at a different rate than those who didn’t. It turned out that the over 1,200 people taking medically-prescribed oral CBD for epilepsy treatment did not test positive for COVID-19 as often as people with similar backgrounds who were not taking CBD.

But the effects of these compounds, the authors noted, are contingent on dosing and purity. After all, commercial products containing cannabinoids are not always pure and reliable. More research is needed to determine what role cannabinoids can play in COVID-19 prevention and treatment.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.