Study: Metformin Shows Efficacy Preventing Development of Long COVID


Investigators found that individuals who received metformin were approximately 40% less likely to develop long COVID than those who received a placebo.

Metformin may prevent the development of long COVID, according to the results of a study published in The Lancet Infectious Diseases.1

pills on the table | Image Credit: Valdemar -

Valdemar -

Investigators from the University of Minnesota aimed to determine whether early outpatient treatment of COVID-19 with metformin, ivermectin, or fluvoxamine could prevent the development of long COVID, a chronic illness that affects up to 10% of those who have had COVID-19.1

“The results of this study are important because long COVID can have a significant impact on [individual’s] lives,” Carolyn Bramante, MD, an assistant professor at the University of Minnesota Medical School, said in a statement. “Metformin is an inexpensive, safe, and widely available drug, and its use as a preventive measure could have significant public health implications.”1

Metformin is a drug that is commonly used to treat diabetes. Investigators used a simulator to predict metformin’s ability to stop the virus. The simulator was developed by the University of Minnesota Medical School and College of Science and Engineering Biomedical Engineering faculty.1

The model has been shown to be highly accurate and can successfully predict outcomes, which include the failure of hydroxychloroquine and the success of remdesivir before the results of clinical trials were announced.1

In this study COVID-OUT (NCT04510194), investigators included more than 1200 individuals randomized to receive either metformin or a placebo and an additional subset who received ivermectin, fluvoxamine, or their placebos.1 Individuals in the study were enrolled from December 30, 2020, to January 28, 2022.2 Individuals were aged 30 to 85 years and qualified as either overweight or obese.

Investigators gave individuals at least 1 survey after the assessment for long COVID at day 180.1 Approximately 95% of individuals completed at least 9 months of follow-up, 56.1% were female, and 7% of women were pregnant.2

More than 1100 of the individuals reported symptoms for up to 10 months after their initial COVID-19 diagnosis.1 Overall, only 8.3% of individuals reported a long COVID diagnosis by day 300, with 6.3% of individuals receiving metformin reporting a diagnosis.2

Investigators found that individuals who received metformin were approximately 40% less likely to develop long COVID than those who received the identical-looking placebo.1 Furthermore, for individuals who started metformin no less than 4 days after their COVID symptoms started, metformin decreased the risk of long COVID by 63%.1

Investigators found that the effect was consistent across different demographic populations and across multiple variants, which included the Omicron variant.1

They also found that ivermectin and fluvoxamine did not prevent long COVID.1

“This long-term outcome from a randomized trial is high-quality evidence that metformin prevents harm from the SARS-CoV-2 virus,” Bramante said in the statement. “While half of our trial had been vaccinated, none had been previously infected with the COVID-19 virus. Further research could show whether it is also effective in those with previous infection or in adults with lower body mass index.”1


1. Study shows metformin lowers the risk of getting long COVID. News release. EurekAlert. June 9, 2023. Accessed June 16, 2023.

2. Bramante CT, Buse JB, Liebovitz DM, Nicklas JM, et al. Outpatient treatment of COVID-19 and incidence of post-COVID-19 condition over 10 months (COVID-OUT): a multicentre, randomised, quadruple-blind, parallel-group, phase 3 trial. Lancet Infect Dis. 2023;S1473-3099(23)00299-2. doi:10.1016/S1473-3099(23)00299-2

Related Videos
pharmacy oncology, Image Credit: © Konstantin Yuganov -
Mayo Clinic oncology pharmacy
Testicular cancer and prostate cancer concept. | Image Credit: kenchiro168 -
Medicine tablets on counting tray with counting spatula at pharmacy | Image Credit: sutlafk -
Capsules medicine and white medicine bottles on table | Image Credit: Satawat -
Human cell or Embryonic stem cell microscope background | Image Credit: Anusorn -
Concept of health care, pharmaceutical business, drug prices, pharmacy, medicine and economics | Image Credit: Oleg -
© 2024 MJH Life Sciences

All rights reserved.