box of glucophage metformin pills

Metformin, a common and inexpensive drug used to treat diabetes, protected people with Covid from getting long Covid in a study published in The Lancet.

The study is a preprint, so it has not been peer-reviewed. But it has caused some excitement because it’s a second medication that seems to reduce long Covid. Paxlovid, a common treatment for people who just were infected with Covid, also seems to have an effect on long Covid, reducing the incidence of long Covid by 25 percent in a Veterans Affairs study posted last fall. But metformin seems to perform better, according to the new study.

Metformin is a generic sold as Riomet, Glumetza, Glucophage or Fortamet. It is used to manage blood sugar levels in diabetics. It has a few side effects but is generally considered safe, and is widely used and inexpensive. (Of course it, like any medication, should be used only in consultation with a medical professional.) It is available by prescription, and can be obtained on the web through such sites as, which bills metformin as a longevity medication. Metformin is in vogue in some circles in Silicon Valley as an anti-aging cure, CNBC has reported.

The metformin long Covid study, of over 1,000 people, assessed metformin; ivermectin, an antiparasitic drug; and fluvoxamine, an antidepressant; a combination of metformin plus one or the other drug; and placebos for a control. Neither ivermectin nor fluvoxamine had an effect on long Covid, the study found.

Long Covid is an incompletely defined series of symptoms and conditions that persist after an initial Covid infection. Because of the loose definition, it’s hard to say how many people have it, but generally estimates are from 10 to 30 percent of people who get Covid. Long Covid has disabled millions of people worldwide, and seriously affected many who are not judged to be completely disabled.

The study classified people as having long Covid if they reported receiving a diagnosis from a medical provider.

Breakthrough for long Covid

Dr. Eric Topol, a respected Scripps research physician, writes over at his Ground Truths Substack: “Until now the only way we knew that Long Covid could be prevented was to not get Covid. That’s still the case. But a new randomized, placebo-controlled trial of metformin has yielded exciting results — the first drug to be shown to help prevent Long Covid. Over a thousand people with mild-to-moderate Covid were randomly assigned to 2 weeks of metformin (500 mg pills, 1 on day 1, twice a day for 4 days, then 500 mg in AM and 1000 mg in PM for 9 days) or placebo. There was a 42% reduction of subsequent Long Covid … which corresponds to an absolute decrease of 4.3%, from 10.6% reduced to 6.3%.”

He added: “As I’ve written in the past, I don’t use the term “breakthrough” lightly. Besides Paxlovid, that I initially wrote about in 2021 here, and the new anti-obesity drugs here, I’m reluctant to go there. But to see such a pronounced benefit in the current randomized trial of metformin, in the context of it being so safe and low cost, I’d give it a breakthrough categorization. Another way to put it, that unless or until there are data to the contrary, if I got Covid, I’d take metformin for 2 weeks at the doses used in this trial.”

Jeanne Pinder

Jeanne Pinder  is the founder and CEO of ClearHealthCosts. She worked at The New York Times for almost 25 years as a reporter, editor and human resources executive, then volunteered for a buyout and founded...