Metformin reduces Long COVID

Blue Metformin Pill on Table

Treating COVID with Metformin Reduces Long COVID Rates


Date: June 9, 2023

Contact: Macy Uustal,, 954-651-0665

Minneapolis, MN –— A new study published today in The Lancet Infectious Diseases found a 41% reduction in Long COVID rates among people who used metformin at the time of COVID infection. The trial also saw a 42% reduction in emergency room visits, hospitalizations, or death among COVID-19 patients who started metformin treatment.

In the COVID-OUT study, researchers from multiple academic institutions tested the effectiveness of three generic medications—metformin, ivermectin and fluvoxamine—in adults who had been diagnosed with COVID-19 within the last three days. The randomized, quadruple-blinded, placebo-controlled clinical trial was the first in the country to study whether these medications could prevent severe outcomes and Long COVID. The trial found that people who took metformin within seven days after the onset of COVID symptoms were 41% less likely to experience Long COVID than those who had placebo—with a 63% reduction if metformin wasstarted within four days.

“The results of this study are important because Long COVID can have a significant impact on people’s lives,” said Carolyn Bramante, MD, principal investigator and an assistant professor at the University of Minnesota Medical School. “Metformin is an inexpensive, safe and widely available drug, and its use as a preventive measure could have significant public health implications.”

Parsemus Metformin Long CovidPrevious data suggested that metformin’s anti-inflammatory and anti-infectious properties could treat COVID-19 infection. The antiviral effect was confirmed in a recent analysis of the viral load of COVID-OUT study participants, which is currently available as a preprint. Researchers reported a 3.6-fold decrease in the SARS-CoV-2 virus level in people who received metformin instead of placebo.

Three years into the pandemic, more than 6.8 million people worldwide have died of the virus, and countless people still suffer from Long COVID. As the first COVID treatment proven to reduce Long COVID in a randomized controlled trial, metformin is safe, accessible and low-cost. Metformin is also one of the most commonly prescribed medications in the United States and globally, taken by more than 150 million people each year. This new treatment option is especially important for the approximately one in three patients who cannot take Paxlovid (Pfizer’s groundbreaking COVID treatment) because of conflicting medications or health conditions.

“Access to affordable COVID treatment is a global justice issue. We hope the U.S. and other nations update their guidelines to include metformin as a treatment option for people with COVID-19,” added Elaine Lissner, founder and trustee of the Parsemus Foundation, a research funder part of the nonprofit coalition funding the trial. “This would be the first universally available treatment, giving more people a tool to combat the disproportionate impact of this disease.”


The Parsemus Foundation works to create meaningful improvements in human and animal health and welfare by advancing innovative and neglected medical research. The foundation has supported rigorous clinical studies on the effectiveness of existing medications to treat COVID infection, including enrollment support and bilingual outreach for the University of Minnesota’s COVID-OUT trial. For more information, see

Tell us what you think

This form does not collect your email address. If you would like us to respond, please send questions to
This field is for validation purposes and should be left unchanged.
We’re sorry, you are not eligible for the nationwide COVID-OUT or ACTIV-6 studies, but you may be eligible for other federal trials:

And if you don’t find a match there, this slightly more complex clinical trials finder includes studies sponsored by companies as well:

Trials Today