These Common Meds May Be Helping COVID Spread in Your Body, Scientists Say

A new COVID variant has landed in the U.S. after surging all spring in China, and scientists are warning that it’s “more transmissible” than other strains of the virus that have been circulating. This could be especially dangerous news for those taking common anti-inflammatory drugs, as a new study has found that the medications can help the flu, COVID, and other viruses spread more easily in the body.

RELATED: Doctors Warn “More Transmissible” COVID Variant Is in the U.S. After a Surge in China.

Anti-inflammatory drugs may help COVID and the flu spread in your body.

The study, published in the journal NAR Molecular Medicine, looked at a class of drugs known as Janus kinase inhibitors, or JAKs.

These medications “help block immune system signals in the body that can lead to swelling (inflammation) and pain in conditions like rheumatoid arthritis, ulcerative colitis, and psoriatic arthritis,” explains Drugs.com. “They work by blocking enzymes that lead to overactivity of the immune system.” You may know them by the common brand names Rinvoq, Xeljanz, Olumiant, Cibinqo, and others.

However, the study researchers found that JAK inhibitors “suppress an important immune signalling pathway that helps protect healthy cells from viral attacks,” said first study author Erlend Ravlo, a PhD research fellow at the Norwegian University of Science and Technology (NTNU), according to a press release. By slowing or stopping the genes that respond to infections, it allows a virus to spread more easily in the body.

“Although JAK inhibitors are effective in the treatment of inflammation, this shows that they can pose a hidden risk for patients who have latent or active viral infections,” Ravlo noted.

To arrive at these findings, the scientists studied human lung, eye, and brain cells, as well as “laboratory-created mini-organs,” states the press release. They then used “advanced techniques in virology, organoid technology, and gene expression analysis.”

“Among the viruses that more easily affect the body with the help of these drugs are Rift Valley fever virus, influenza A, adenovirus, and SARS-CoV-2, the virus that causes COVID-19,” explained lead study author Denis Kainov, a professor at the Department of Clinical and Molecular Medicine at NTNU.

RELATED: 85% of Unvaccinated Women Will Likely Get This Virus—And New Research Links It to Heart Disease.

JAK inhibitors may increase the risk of other infections, too.

Other studies have also looked at the connection between JAK inhibitors and an increased risk of infection.

Notably, a 2025 meta-analysis of 69 studies found that, compared to placebo groups, those taking these drugs had a “significantly increased risk” of developing infections, including the common cold, herpes, tuberculosis, urinary tract infections, yeast infections, hepatitis, pneumonia, respiratory tract infections, and folliculitis.

More specifically, a 2021 peer-reviewed publication found that use of JAK inhibitors was “associated with greater odds of having a worse COVID-19 severity.”

Is it dangerous to take JAK inhibitors?

Researchers from the latest study hope their findings will influence doctors to take extra caution when prescribing JAK inhibitors, especially during viral outbreaks. However, they also point out that the immunosuppressive effect they discovered could “be useful in controlled environments, such as in the development of vaccines or screening of antiviral drugs,” states the press release.

“We recommend further studies to better understand how the drugs can be used optimally, especially during virus outbreaks or pandemics,” concluded study co-author Aleksandr Ianevski, an NTNU researcher.

If you’re concerned about taking a JAK inhibitor, speak to your healthcare provider directly.